How can you detect the version of a browser?

Question

I've been searching around for code that would let me detect if the user visiting the website has Firefox 3 or 4. All I have found is code to detect the type of browser but not the version.

How can I detect the version of a browser like this?

Injury

I recommend to setup on a proven library instead of small chunk code: * github.com/bestiejs/platform.js * github.com/ded/bowser both having > 1,000 stars – Marteena

page not found. – Sisterinlaw

Answer 1

You can see what the browser says, and use that information for logging or testing multiple browsers.

navigator.sayswho= (function(){
    var ua= navigator.userAgent;
    var tem; 
    var M= ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || [];
    if(/trident/i.test(M[1])){
        tem=  /\brv[ :]+(\d+)/g.exec(ua) || [];
        return 'IE '+(tem[1] || '');
    }
    if(M[1]=== 'Chrome'){
        tem= ua.match(/\b(OPR|Edge)\/(\d+)/);
        if(tem!= null) return tem.slice(1).join(' ').replace('OPR', 'Opera');
    }
    M= M[2]? [M[1], M[2]]: [navigator.appName, navigator.appVersion, '-?'];
    if((tem= ua.match(/version\/(\d+)/i))!= null) M.splice(1, 1, tem[1]);
    return M.join(' ');
})();

console.log(navigator.sayswho); // outputs: `Chrome 62`

Ironstone

just discovered serious issue downgrading broswer IE11 to IE10 navigatior user agent showing Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; WOW64; Trident/6.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; InfoPath.3; .NET4.0C; .NET4.0E) from string its IE7 with trident/6.0 be careful – Verda

Shouldn't the 2nd to last line be M[1] = tem[1] rather than M[2]? With the code as it currently stands, the Opera 12.14 user agent string Opera/9.80 (Windows NT 6.0) Presto/2.12.388 Version/12.14 returns the result Opera 9.80 12.14. IMO, the correct result would be Opera 12.14 which would be accomplished by my suggestion. – Beamon

It would be helpful if this answer included output examples. I can't tell what strings to expect from the function. – Mammoth

Didn't account for Edge yet: tem = ua.match(/\b(OPR|Edge)\/(\d+)/i); if (tem != null) return {name : tem[1] === 'OPR' ? 'Opera' : tem[1], version : tem[2]}; – Lh

This script incorrectly reports browser Chrome version 4.0 for the internal Facebook browser (launched when you click web links within the Facebook app on Android). The useragent string looks something like: Mozilla/5.0 (Linux; Android 5.0; Nexus 9 Build/LRX21R; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/45.0.2454.95 Safari/537.36 [FB_IAB/FB4A;FBAV/50.0.0.10.54;] This is a very prominent user agent unfortunately so can't really ignore it... – Pesthouse

any snippet for detecting android or ios low version browsers? – Purulent

Still gets wrong version on many android user agent strings. Random example: Mozilla/5.0 (Linux; Android 8.0.0; SM-G965U Build/R16NW; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/71.0.3578.98 Mobile Safari/537.36 – Eliaeliades

There are libraries that do this, viz bowser, and as a general rule you shouldn't reinvent the wheel if you don't have to. – Astrobiology

This version don't have the decimal part. For Safari, this is very relevant. – Interlace

Not recognize EDGE based on chrome (+2019) - example ua: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.92 Safari/537.36 Edg/81.0.416.53 – Cycloplegia

You could use the regex "Edge?" for optional "e". This will detect both versions of Edge. ("Edge" / legacy and "Edg" / chromium). Output e.g.: "Edge 18" or "Edg 84" (which is the chrome version too.) You can do whatever you want with this string. e.g. Replace with a more readable name or adding (legacy / chromium). – Woad

I've also been caught out by the WebView problem where the Chrome/92.0 overrides the version number and replaces by Version/4.0 – Hyehyena

This answer must be updated to detect "Microsoft Edge" : : How can you detect the version of a browser? – Deviled

Answer 2

This is an improvement on Kennebec's answer.

mbrowser=function(){
    this.spec_string=   navigator.userAgent;
    this.name=          this.get_name();
    this.version=       this.get_version();
    };

mbrowser.prototype.get_name=function(){
    var spec_string=this.spec_string;

    var matches=spec_string.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || [];
    
    // Work with the matches.
    matches=matches[2]? [matches[1], matches[2]]: [navigator.appName, navigator.appVersion, '-?'];
        
    // Trident.
    if(/trident/i.test(matches[1])){
        var temp=/\brv[ :]+(\d+)/g.exec(spec_string) || [];
        return 'IE';
        }
    
    // Chrome.
    if(matches[1]==='Chrome'){
        var temp=spec_string.match(/\bOPR|Edge\/(\d+)/)
        if(temp!=null)   {return 'Opera';}
        }   

    if((temp=spec_string.match(/version\/(\d+)/i))!=null){
        matches.splice(1,1,temp[1]);
        }
                                                                                                                       
    var name=matches[0];

    return name;
    };


mbrowser.prototype.get_version=function(){
    var spec_string=this.spec_string;

    var matches=spec_string.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || []; 

    // Work with the matches.
    matches=matches[2]? [matches[1], matches[2]]: [navigator.appName, navigator.appVersion, '-?'];

    // Trident.
    if(/trident/i.test(matches[1])){
        var temp=/\brv[ :]+(\d+)/g.exec(spec_string) || []; 
        var version=(temp[1]||'');
        return version;
        }   

    // Chrome.
    if(matches[1]==='Chrome'){
        var temp=spec_string.match(/\bOPR|Edge\/(\d+)/)
        var version=temp[1];
        if(temp!=null)   {return version;}
        }   

    if((temp=spec_string.match(/version\/(\d+)/i))!=null){
        matches.splice(1,1,temp[1]);                                                                                   
        }

    var version=matches[1];

    return version;
    };

// m=module.
var browser=new mbrowser();
console.log(browser.name);    // Chrome
console.log(browser.version); // 109

This code deduces browser name and number from the spec_string (navigator.userAgent). But there are all kinds of spec_strings out there with their respective browser name and number. And I'm not in a situation to check but a tiny proportion of them. It would be great if you could post a spec_string whose resulting browser name and number you know. I can then update the code accordingly.

I would then slowly build up a list of spec_string items in the following manner.

'spec_string1'=>[name,number],
'spec_string2'=>[name,number],

Then in the future, whenever a change is made to the code it can automatically be tested on all known spec_string conversions.

We can do this together.

Sisterinlaw

(some platforms - os x for instance - will give a different output for navigator.userAgent and you can't recognise Opera browser by 'Opera' string but instead with 'OPR'). – Wreckfish

get_browser and get_browser_version return incorrect details inside the 'if trident' and 'if chrome' conditionals if tem!=null – Polonaise

returns chrome for edge browser – Clitoris

Could you guys send me a spec_string/userAgent, who's browser name and version you know? – Sisterinlaw

Answer 3

Here are several prominent libraries that handle browser detection as of May 2019.

Bowser by lancedikson - 3,761★s - Last updated May 26, 2019 - 4.8KB

var result = bowser.getParser(window.navigator.userAgent);
console.log(result);
document.write("You are using " + result.parsedResult.browser.name +
               " v" + result.parsedResult.browser.version + 
               " on " + result.parsedResult.os.name);

<script src="https://unpkg.com/[email protected]/es5.js"></script>

*supports Edge based on Chromium

---

Platform.js by bestiejs - 2,250★s - Last updated Oct 30, 2018 - 5.9KB

console.log(platform);
document.write("You are using " + platform.name +
               " v" + platform.version + 
               " on " + platform.os);

<script src="https://cdnjs.cloudflare.com/ajax/libs/platform/1.3.5/platform.min.js"></script>

jQuery Browser by gabceb - 504★s - Last updated Nov 23, 2015 - 1.3KB

console.log($.browser)
document.write("You are using " + $.browser.name +
               " v" + $.browser.versionNumber + 
               " on " + $.browser.platform);

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery-browser/0.1.0/jquery.browser.min.js"></script>

Detect.js (Archived) by darcyclarke - 522★s - Last updated Oct 26, 2015 - 2.9KB

var result = detect.parse(navigator.userAgent);
console.log(result);
document.write("You are using " + result.browser.family +
               " v" + result.browser.version + 
               " on " + result.os.family);

<script src="https://cdnjs.cloudflare.com/ajax/libs/Detect.js/2.2.2/detect.min.js"></script>

Browser Detect (Archived) by QuirksMode - Last updated Nov 14, 2013 - 884B

console.log(BrowserDetect)
document.write("You are using " + BrowserDetect.browser +
               " v" + BrowserDetect.version + 
               " on " + BrowserDetect.OS);

<script src="https://kylemit.github.io/libraries/libraries/BrowserDetect.js"></script>

---

Notable Mentions:

• WhichBrowser - 1,355★s - Last updated Oct 2, 2018
• Modernizr - 23,397★s - Last updated Jan 12, 2019 - To feed a fed horse, feature detection should drive any canIuse style questions. Browser detection is really just for providing customized images, download files, or instructions for individual browsers.

Further Reading

• Stack Overflow - Browser detection in JavaScript?
• Stack Overflow - How to detect Safari, Chrome, IE, Firefox and Opera browser?

Cricket

Answer 4

This combines kennebec's (K) answer with Hermann Ingjaldsson's (H) answer:

• Maintains original answer's minimal code. (K)
• Works with Microsoft Edge (K)
• Extends the navigator object instead of creating a new variable/object. (K)
• Separates browser version and name into independent child objects. (H)

 

    navigator.browserSpecs = (function(){
        var ua = navigator.userAgent, tem, 
            M = ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || [];
        if(/trident/i.test(M[1])){
            tem = /\brv[ :]+(\d+)/g.exec(ua) || [];
            return {name:'IE',version:(tem[1] || '')};
        }
        if(M[1]=== 'Chrome'){
            tem = ua.match(/\b(OPR|Edge)\/(\d+)/);
            if(tem != null) return {name:tem[1].replace('OPR', 'Opera'),version:tem[2]};
        }
        M = M[2]? [M[1], M[2]]: [navigator.appName, navigator.appVersion, '-?'];
        if((tem = ua.match(/version\/(\d+)/i))!= null)
            M.splice(1, 1, tem[1]);
        return {name:M[0], version:M[1]};
    })();

    console.log(navigator.browserSpecs); //Object { name: "Firefox", version: "42" }

    if (navigator.browserSpecs.name == 'Firefox') {
        // Do something for Firefox.
        if (navigator.browserSpecs.version > 42) {
            // Do something for Firefox versions greater than 42.
        }
    }
    else {
        // Do something for all other browsers.
    }

Abney

what meaninful name could we have given to M, and tem? I'm thinking on broserName and version?? – Horripilate

Answer 5

The bowser JavaScript library offers this functionality.

if (bowser.msie && bowser.version <= 6) {
  alert('Hello China');
}

It seems to be well maintained.

Gleeman

Answer 6

Use this: http://www.quirksmode.org/js/detect.html

alert(BrowserDetect.browser); // will say "Firefox"
alert(BrowserDetect.version); // will say "3" or "4"

Thinking

Outdated reference, no longer supported -"This page used to contain my own browser detect script, but I found that I do not have enough time to keep it up to date. Therefore I removed it." – Ihab

Answer 7

I was looking for a solution for myself, since jQuery 1.9.1 and above have removed the $.browser functionality. I came up with this little function that works for me. It does need a global variable (I've called mine _browser) in order to check which browser it is. I've written a jsfiddle to illustrate how it can be used, of course it can be expanded for other browsers by just adding a test for _browser.foo, where foo is the name of the browser. I did just the popular ones.

detectBrowser()

_browser = {};

function detectBrowser() {
  var uagent = navigator.userAgent.toLowerCase(),
      match = '';
    
  _browser.chrome  = /webkit/.test(uagent)  && /chrome/.test(uagent)      &&
                     !/edge/.test(uagent);

  _browser.firefox = /mozilla/.test(uagent) && /firefox/.test(uagent);

  _browser.msie    = /msie/.test(uagent)    || /trident/.test(uagent)     ||
                     /edge/.test(uagent);

  _browser.safari  = /safari/.test(uagent)  && /applewebkit/.test(uagent) &&
                     !/chrome/.test(uagent);

  _browser.opr     = /mozilla/.test(uagent) && /applewebkit/.test(uagent) &&
                     /chrome/.test(uagent)  && /safari/.test(uagent)      &&
                     /opr/.test(uagent);

  _browser.version = '';
    
  for (x in _browser) {
    if (_browser[x]) {

      match = uagent.match(
                new RegExp("(" + (x === "msie" ? "msie|edge" : x) + ")( |\/)([0-9]+)")
              );

      if (match) {
        _browser.version = match[3];
      } else {
        match = uagent.match(new RegExp("rv:([0-9]+)"));
        _browser.version = match ? match[1] : "";
      }
      break;
    }
  }
  _browser.opera = _browser.opr;
  delete _browser.opr;
}

detectBrowser();

console.log(_browser)

To check if the current browser is Opera you would do

if (_browser.opera) { // Opera specific code }

Edit Fixed the formatting, fixed the detection for IE11 and Opera/Chrome, changed to browserResult from result. Now the order of the _browser keys doesn't matter. Updated jsFiddle link.

2015/08/11 Edit Added new testcase for Internet Explorer 12 (EDGE), fixed a small regexp problem. Updated jsFiddle link.

Reeve

For new IE Edge(aka Spartan) in Windows 10 it shows that my browser is Chrome 42 --- User agent string: mozilla/5.0 (windows nt 10.0; win64; x64) applewebkit/537.36 (khtml, like gecko) chrome/42.0.2311.135 safari/537.36 edge/12.10240 The browser is chrome 42 – Fireside

Thanks @Fireside for your comment and provided sample uagent, since I don't have Edge or Win10. Just going from it I have updated the code in the jsFiddle to reflect that. If you want to test with the sample uagent you gave me just go to this fiddle. Let me know if there is something wrong. – Reeve

Answer 8

function BrowserCheck()
{
    var N= navigator.appName, ua= navigator.userAgent, tem;
    var M= ua.match(/(opera|chrome|safari|firefox|msie|trident)\/?\s*(\.?\d+(\.\d+)*)/i);
    if(M && (tem= ua.match(/version\/([\.\d]+)/i))!= null) {M[2]=tem[1];}
    M= M? [M[1], M[2]]: [N, navigator.appVersion,'-?'];
    return M;
}

This will return an array, first element is the browser name, second element is the complete version number in string format.

Shroyer

Answer 9

This is a Update on Fzs2 & kennebec For New Edge Chromium

function get_browser() {
    var ua=navigator.userAgent,tem,M=ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || []; 
    if(/trident/i.test(M[1])){
        tem=/\brv[ :]+(\d+)/g.exec(ua) || []; 
        return {name:'IE',version:(tem[1]||'')};
        }   
    if(M[1]==='Chrome'){
        tem=ua.match(/\bEdg\/(\d+)/)
        if(tem!=null)   {return {name:'Edge(Chromium)', version:tem[1]};}
        tem=ua.match(/\bOPR\/(\d+)/)
        if(tem!=null)   {return {name:'Opera', version:tem[1]};}
        }   
    M=M[2]? [M[1], M[2]]: [navigator.appName, navigator.appVersion, '-?'];
    if((tem=ua.match(/version\/(\d+)/i))!=null) {M.splice(1,1,tem[1]);}
    return {
      name: M[0],
      version: M[1]
    };
 }

var browser=get_browser(); // browser.name = 'Edge(Chromium)'
                           // browser.version = '86'

console.log(browser);

Maple

Answer 10

jQuery can handle this quite nice (jQuery.browser)

var ua = $.browser;
if ( ua.mozilla && ua.version.slice(0,3) == "1.9" ) {
    alert( "Do stuff for firefox 3" );
}

EDIT: As Joshua wrote in his comment below, jQuery.browser property is no longer supported in jQuery since version 1.9 (read jQuery 1.9 release notes for more details). jQuery development team recommends using more complete approach like adapting UI with Modernizr library.

Enclasp

jQuery 1.9 has removed $.browser support, so this is no longer an option. – Sketch

Joshua - yes, you are right; at least they left jQuery.support property for detecting browser support for certain features (but I'm not sure if this the case of initial question) – Enclasp

Answer 11

In pure Javascript you can do a RegExp match on the navigator.userAgent to find the Firefox version:

var uMatch = navigator.userAgent.match(/Firefox\/(.*)$/),
    ffVersion;
if (uMatch && uMatch.length > 1) {
    ffVersion = uMatch[1];
}

ffVersion will be undefined if not a Firefox browser.

See working example →

Languor

Answer 12

Look at navigator.userAgent - Firefox/xxx.xxx.xxx is specified right at the end.

Glamorize

Answer 13

Detecting Browser and Its version

This code snippet is based on the article from MDN. Where they gave a brief hint about various keywords that can be used to detect the browser name.

I have done few changes to detect browsers like Edge and UCBrowser

getBrowser = () => {
    const userAgent = navigator.userAgent;
    let browser = "unkown";
    // Detect browser name
    browser = (/ucbrowser/i).test(userAgent) ? 'UCBrowser' : browser;
    browser = (/edg/i).test(userAgent) ? 'Edge' : browser;
    browser = (/googlebot/i).test(userAgent) ? 'GoogleBot' : browser;
    browser = (/chromium/i).test(userAgent) ? 'Chromium' : browser;
    browser = (/firefox|fxios/i).test(userAgent) && !(/seamonkey/i).test(userAgent) ? 'Firefox' : browser;
    browser = (/; msie|trident/i).test(userAgent) && !(/ucbrowser/i).test(userAgent) ? 'IE' : browser;
    browser = (/chrome|crios/i).test(userAgent) && !(/opr|opera|chromium|edg|ucbrowser|googlebot/i).test(userAgent) ? 'Chrome' : browser;;
    browser = (/safari/i).test(userAgent) && !(/chromium|edg|ucbrowser|chrome|crios|opr|opera|fxios|firefox/i).test(userAgent) ? 'Safari' : browser;
    browser = (/opr|opera/i).test(userAgent) ? 'Opera' : browser;

    // detect browser version
    switch (browser) {
        case 'UCBrowser': return `${browser}/${browserVersion(userAgent,/(ucbrowser)\/([\d\.]+)/i)}`;
        case 'Edge': return `${browser}/${browserVersion(userAgent,/(edge|edga|edgios|edg)\/([\d\.]+)/i)}`;
        case 'GoogleBot': return `${browser}/${browserVersion(userAgent,/(googlebot)\/([\d\.]+)/i)}`;
        case 'Chromium': return `${browser}/${browserVersion(userAgent,/(chromium)\/([\d\.]+)/i)}`;
        case 'Firefox': return `${browser}/${browserVersion(userAgent,/(firefox|fxios)\/([\d\.]+)/i)}`;
        case 'Chrome': return `${browser}/${browserVersion(userAgent,/(chrome|crios)\/([\d\.]+)/i)}`;
        case 'Safari': return `${browser}/${browserVersion(userAgent,/(safari)\/([\d\.]+)/i)}`;
        case 'Opera': return `${browser}/${browserVersion(userAgent,/(opera|opr)\/([\d\.]+)/i)}`;
        case 'IE': const version = browserVersion(userAgent,/(trident)\/([\d\.]+)/i);
            // IE version is mapped using trident version 
            // IE/8.0 = Trident/4.0, IE/9.0 = Trident/5.0
            return version ? `${browser}/${parseFloat(version) + 4.0}` : `${browser}/7.0`;
        default: return `unknown/0.0.0.0`;
    }
}

browserVersion = (userAgent,regex) => {
    return userAgent.match(regex) ? userAgent.match(regex)[2] : null;
}

console.log(getBrowser());

Nedneda

Answer 14

I wrote a version detector based on Hermann Ingjaldsson's answer, but more robust and which returns an object with name/version data in it. It covers the major browsers but I don't bother with the plethora of mobile ones and minor ones:

function getBrowserData(nav) {
    var data = {};

    var ua = data.uaString = nav.userAgent;
    var browserMatch = ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*([\d\.]+)/i) || [];
    if (browserMatch[1]) { browserMatch[1] = browserMatch[1].toLowerCase(); }
    var operaMatch = browserMatch[1] === 'chrome';
    if (operaMatch) { operaMatch = ua.match(/\bOPR\/([\d\.]+)/); }

    if (/trident/i.test(browserMatch[1])) {
        var msieMatch = /\brv[ :]+([\d\.]+)/g.exec(ua) || [];
        data.name = 'msie';
        data.version = msieMatch[1];
    }
    else if (operaMatch) {
        data.name = 'opera';
        data.version = operaMatch[1];
    }
    else if (browserMatch[1] === 'safari') {
        var safariVersionMatch = ua.match(/version\/([\d\.]+)/i);
        data.name = 'safari';
        data.version = safariVersionMatch[1];
    }
    else {
        data.name = browserMatch[1];
        data.version = browserMatch[2];
    }

    var versionParts = [];
    if (data.version) {
        var versionPartsMatch = data.version.match(/(\d+)/g) || [];
        for (var i=0; i < versionPartsMatch.length; i++) {
            versionParts.push(versionPartsMatch[i]);
        }
        if (versionParts.length > 0) { data.majorVersion = versionParts[0]; }
    }
    data.name = data.name || '(unknown browser name)';
    data.version = {
        full: data.version || '(unknown full browser version)',
        parts: versionParts,
        major: versionParts.length > 0 ? versionParts[0] : '(unknown major browser version)'
    };

    return data;
};

It can then be used like this:

var brData = getBrowserData(window.navigator || navigator);
console.log('name: ' + brData.name);
console.log('major version: ' + brData.version.major);
// etc.

Hospitium

Answer 15

For this you need to check the value of navigator.appVersion or navigator.userAgent Try using:

console.log(navigator.appVersion)

Fording

Answer 16

<script type="text/javascript">
var version = navigator.appVersion;
alert(version);
</script>

Rezzani

FYI appVersion has been deprecated see developer.mozilla.org/en-US/docs/Web/API/Navigator/… – Doublestop

Answer 17

var nVer = navigator.appVersion;
var nAgt = navigator.userAgent;
var browserName  = navigator.appName;
var fullVersion  = ''+parseFloat(navigator.appVersion);
var majorVersion = parseInt(navigator.appVersion,10);
var nameOffset,verOffset,ix;

// In Opera, the true version is after "Opera" or after "Version"

if ((verOffset=nAgt.indexOf("Opera"))!=-1) {
 browserName = "Opera";
 fullVersion = nAgt.substring(verOffset+6);
 if ((verOffset=nAgt.indexOf("Version"))!=-1)
   fullVersion = nAgt.substring(verOffset+8);
}
// In MSIE, the true version is after "MSIE" in userAgent

else if ((verOffset=nAgt.indexOf("MSIE"))!=-1) {
 browserName = "Microsoft Internet Explorer";
 fullVersion = nAgt.substring(verOffset+5);
}
// In Chrome, the true version is after "Chrome"

else if ((verOffset=nAgt.indexOf("Chrome"))!=-1) {
 browserName = "Chrome";
 fullVersion = nAgt.substring(verOffset+7);
}
// In Safari, the true version is after "Safari" or after "Version"

else if ((verOffset=nAgt.indexOf("Safari"))!=-1) {
 browserName = "Safari";
 fullVersion = nAgt.substring(verOffset+7);
 if ((verOffset=nAgt.indexOf("Version"))!=-1)
   fullVersion = nAgt.substring(verOffset+8);
}
// In Firefox, the true version is after "Firefox"

else if ((verOffset=nAgt.indexOf("Firefox"))!=-1) {
 browserName = "Firefox";
 fullVersion = nAgt.substring(verOffset+8);
}
// In most other browsers, "name/version" is at the end of userAgent

else if ( (nameOffset=nAgt.lastIndexOf(' ')+1) <
          (verOffset=nAgt.lastIndexOf('/')) )
{
 browserName = nAgt.substring(nameOffset,verOffset);
 fullVersion = nAgt.substring(verOffset+1);
 if (browserName.toLowerCase()==browserName.toUpperCase()) {
  browserName = navigator.appName;
 }
}

// trim the fullVersion string at semicolon/space if present

if ((ix=fullVersion.indexOf(";"))!=-1)
   fullVersion=fullVersion.substring(0,ix);
if ((ix=fullVersion.indexOf(" "))!=-1)
   fullVersion=fullVersion.substring(0,ix);

majorVersion = parseInt(''+fullVersion,10);
if (isNaN(majorVersion)) {
 fullVersion  = ''+parseFloat(navigator.appVersion);
 majorVersion = parseInt(navigator.appVersion,10);
}

document.write(''
 +'Browser name  = '+browserName+'<br>'
 +'Full version  = '+fullVersion+'<br>'
 +'Major version = '+majorVersion+'<br>'
 +'navigator.appName = '+navigator.appName+'<br>'
 +'navigator.userAgent = '+navigator.userAgent+'<br>'
)

See the demo here..http://jsfiddle.net/hw4jM/3/

Uticas

Answer 18

I have made a script in ASP code to detect browser, browser version, OS and OS version. The reason for me to do this in ASP was because i want to store the data in a log-database. So I had to detect the browser serverside.

Here is the code:

on error resume next
ua = lcase(Request.ServerVariables("HTTP_USER_AGENT"))
moz = instr(ua,"mozilla")  
ffx = instr(ua,"firefox")  
saf = instr(ua,"safari")
crm = instr(ua,"chrome") 
max = instr(ua,"maxthon") 
opr = instr(ua,"opera")
ie4 = instr(ua,"msie 4") 
ie5 = instr(ua,"msie 5") 
ie6 = instr(ua,"msie 6") 
ie7 = instr(ua,"msie 7") 
ie8 = instr(ua,"trident/4.0")
ie9 = instr(ua,"trident/5.0")

if moz>0 then 
    BrowserType = "Mozilla"
    BrVer = mid(ua,moz+8,(instr(moz,ua," ")-(moz+8)))
end if
if ffx>0 then 
    BrowserType = "FireFox"
    BrVer = mid(ua,ffx+8)
end if
if saf>0 then 
    BrowserType = "Safari"
    BrVerPlass = instr(ua,"version")
    BrVer = mid(ua,BrVerPlass+8,(instr(BrVerPlass,ua," ")-(BrVerPlass+8)))
end if
if crm>0 then 
    BrowserType = "Chrome"
    BrVer = mid(ua,crm+7,(instr(crm,ua," ")-(crm+7)))
end if
if max>0 then 
    BrowserType = "Maxthon"
    BrVer = mid(ua,max+8,(instr(max,ua," ")-(max+8)))
end if
if opr>0 then 
    BrowserType = "Opera"
    BrVerPlass = instr(ua,"presto")
    BrVer = mid(ua,BrVerPlass+7,(instr(BrVerPlass,ua," ")-(BrVerPlass+7)))
end if
if ie4>0 then 
    BrowserType = "Internet Explorer"
    BrVer = "4"
end if
if ie5>0 then 
    BrowserType = "Internet Explorer"
    BrVer = "5"
end if
if ie6>0 then 
    BrowserType = "Internet Explorer"
    BrVer = "6"
end if
if ie7>0 then 
    BrowserType = "Internet Explorer"
    BrVer = "7"
end if
if ie8>0 then 
    BrowserType = "Internet Explorer"
    BrVer = "8"
    if ie7>0 then BrVer = BrVer & " (in IE7 compability mode)"
end if
if ie9>0 then 
    BrowserType = "Internet Explorer"
    BrVer = "9"
    if ie7>0 then BrVer = BrVer & " (in IE7 compability mode)"
    if ie8>0 then BrVer = BrVer & " (in IE8 compability mode)"
end if

OSSel = mid(ua,instr(ua,"(")+1,(instr(ua,";")-instr(ua,"("))-1)
OSver = mid(ua,instr(ua,";")+1,(instr(ua,")")-instr(ua,";"))-1)

if BrowserType = "Internet Explorer" then
    OSStart = instr(ua,";")
    OSStart = instr(OSStart+1,ua,";")        
    OSStopp = instr(OSStart+1,ua,";")
    OSsel = mid(ua,OSStart+2,(OSStopp-OSStart)-2)
end if

    Select case OSsel
        case "windows nt 6.1"
            OS = "Windows"
            OSver = "7"
        case "windows nt 6.0"
            OS = "Windows"
            OSver = "Vista"
        case "windows nt 5.2"
            OS = "Windows"
            OSver = "Srv 2003 / XP x64"
        case "windows nt 5.1"
            OS = "Windows"
            OSver = "XP"
        case else
            OS = OSSel
    End select

Response.write "<br>" & ua & "<br>" & BrowserType & "<br>" & BrVer & "<br>" & OS & "<br>" & OSver & "<br>"

'Use the variables here for whatever you need........

Mammon

Answer 19

This page seems to have a pretty nice snippet which only uses the appString and appVersion property as a last resort as it claims them to be unreliable with certain browsers. The code on the page is as follows:

var nVer = navigator.appVersion;
var nAgt = navigator.userAgent;
var browserName  = navigator.appName;
var fullVersion  = ''+parseFloat(navigator.appVersion); 
var majorVersion = parseInt(navigator.appVersion,10);
var nameOffset,verOffset,ix;

// In Opera 15+, the true version is after "OPR/" 
if ((verOffset=nAgt.indexOf("OPR/"))!=-1) {
 browserName = "Opera";
 fullVersion = nAgt.substring(verOffset+4);
}
// In older Opera, the true version is after "Opera" or after "Version"
else if ((verOffset=nAgt.indexOf("Opera"))!=-1) {
 browserName = "Opera";
 fullVersion = nAgt.substring(verOffset+6);
 if ((verOffset=nAgt.indexOf("Version"))!=-1) 
   fullVersion = nAgt.substring(verOffset+8);
}
// In MSIE, the true version is after "MSIE" in userAgent
else if ((verOffset=nAgt.indexOf("MSIE"))!=-1) {
 browserName = "Microsoft Internet Explorer";
 fullVersion = nAgt.substring(verOffset+5);
}
// In Chrome, the true version is after "Chrome" 
else if ((verOffset=nAgt.indexOf("Chrome"))!=-1) {
 browserName = "Chrome";
 fullVersion = nAgt.substring(verOffset+7);
}
// In Safari, the true version is after "Safari" or after "Version" 
else if ((verOffset=nAgt.indexOf("Safari"))!=-1) {
 browserName = "Safari";
 fullVersion = nAgt.substring(verOffset+7);
 if ((verOffset=nAgt.indexOf("Version"))!=-1) 
   fullVersion = nAgt.substring(verOffset+8);
}
// In Firefox, the true version is after "Firefox" 
else if ((verOffset=nAgt.indexOf("Firefox"))!=-1) {
 browserName = "Firefox";
 fullVersion = nAgt.substring(verOffset+8);
}
// In most other browsers, "name/version" is at the end of userAgent 
else if ( (nameOffset=nAgt.lastIndexOf(' ')+1) < 
          (verOffset=nAgt.lastIndexOf('/')) ) 
{
 browserName = nAgt.substring(nameOffset,verOffset);
 fullVersion = nAgt.substring(verOffset+1);
 if (browserName.toLowerCase()==browserName.toUpperCase()) {
  browserName = navigator.appName;
 }
}
// trim the fullVersion string at semicolon/space if present
if ((ix=fullVersion.indexOf(";"))!=-1)
   fullVersion=fullVersion.substring(0,ix);
if ((ix=fullVersion.indexOf(" "))!=-1)
   fullVersion=fullVersion.substring(0,ix);

majorVersion = parseInt(''+fullVersion,10);
if (isNaN(majorVersion)) {
 fullVersion  = ''+parseFloat(navigator.appVersion); 
 majorVersion = parseInt(navigator.appVersion,10);
}

document.write(''
 +'Browser name  = '+browserName+'<br>'
 +'Full version  = '+fullVersion+'<br>'
 +'Major version = '+majorVersion+'<br>'
 +'navigator.appName = '+navigator.appName+'<br>'
 +'navigator.userAgent = '+navigator.userAgent+'<br>'
)

Pentecostal

Answer 20

Adding my own implementation of Hermann's answer. I needed OS detection so that's been added. Also includes some ES6 code (because we have a transpiler) that you might need to ES5-ify.

detectClient() {
    let nav = navigator.appVersion,
        os = 'unknown',
        client = (() => {
            let agent = navigator.userAgent,
                engine = agent.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || [],
                build;

            if(/trident/i.test(engine[1])){
                build = /\brv[ :]+(\d+)/g.exec(agent) || [];
                return {browser:'IE', version:(build[1] || '')};
            }

            if(engine[1] === 'Chrome'){
                build = agent.match(/\bOPR\/(\d+)/);

                if(build !== null) {
                    return {browser: 'Opera', version: build[1]};
                }
            }

            engine = engine[2] ? [engine[1], engine[2]] : [navigator.appName, nav, '-?'];

            if((build = agent.match(/version\/(\d+)/i)) !== null) {
                engine.splice(1, 1, build[1]);
            }

            return {
              browser: engine[0],
              version: engine[1]
            };
        })();

    switch (true) {
        case nav.indexOf('Win') > -1:
            os = 'Windows';
        break;
        case nav.indexOf('Mac') > -1:
            os = 'MacOS';
        break;
        case nav.indexOf('X11') > -1:
            os = 'UNIX';
        break;
        case nav.indexOf('Linux') > -1:
            os = 'Linux';
        break;
    }        

    client.os = os;
    return client;
}

Returns: Object {browser: "Chrome", version: "50", os: "UNIX"}

Gynophore

Answer 21

I want to share this code I wrote for the issue I had to resolve. It was tested in most of the major browsers and works like a charm, for me!

It may seems that this code is very similar to the other answers but it modifyed so that I can use it insted of the browser object in jquery which missed for me recently, of course it is a combination from the above codes, with little improvements from my part I made:

(function($, ua){

var M = ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || [],
    tem, 
    res;

if(/trident/i.test(M[1])){
    tem = /\brv[ :]+(\d+)/g.exec(ua) || [];
    res = 'IE ' + (tem[1] || '');
}
else if(M[1] === 'Chrome'){
    tem = ua.match(/\b(OPR|Edge)\/(\d+)/);
    if(tem != null) 
        res = tem.slice(1).join(' ').replace('OPR', 'Opera');
    else
        res = [M[1], M[2]];
}
else {
    M = M[2]? [M[1], M[2]] : [navigator.appName, navigator.appVersion, '-?'];
    if((tem = ua.match(/version\/(\d+)/i)) != null) M = M.splice(1, 1, tem[1]);
    res = M;
}

res = typeof res === 'string'? res.split(' ') : res;

$.browser = {
    name: res[0],
    version: res[1],
    msie: /msie|ie/i.test(res[0]),
    firefox: /firefox/i.test(res[0]),
    opera: /opera/i.test(res[0]),
    chrome: /chrome/i.test(res[0]),
    edge: /edge/i.test(res[0])
}

})(typeof jQuery != 'undefined'? jQuery : window.$, navigator.userAgent);

 console.log($.browser.name, $.browser.version, $.browser.msie); 
// if IE 11 output is: IE 11 true

Jevons

Answer 22

Here this has better compatibility then @kennebec snippet;
will return browser name and version (returns 72 instead of 72.0.3626.96).

Tested on Safari, Chrome, Opera, Firefox, IE, Edge, UCBrowser, also on mobile.

function browser() {
    var userAgent = navigator.userAgent,
        match = userAgent.match(/(opera|chrome|crios|safari|ucbrowser|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || [],
        result = {},
        tem;

    if (/trident/i.test(match[1])) {
        tem = /\brv[ :]+(\d+)/g.exec(userAgent) || [];
        result.name = "Internet Explorer";
    } else if (match[1] === "Chrome") {
        tem = userAgent.match(/\b(OPR|Edge)\/(\d+)/);

        if (tem && tem[1]) {
            result.name = tem[0].indexOf("Edge") === 0 ? "Edge" : "Opera";
        }
    }
    if (!result.name) {
        tem = userAgent.match(/version\/(\d+)/i); // iOS support
        result.name = match[0].replace(/\/.*/, "");

        if (result.name.indexOf("MSIE") === 0) {
            result.name = "Internet Explorer";
        }
        if (userAgent.match("CriOS")) {
            result.name = "Chrome";
        }

    }
    if (tem && tem.length) {
        match[match.length - 1] = tem[tem.length - 1];
    }

    result.version = Number(match[match.length - 1]);

    return result;
}

Inelegance

Answer 23

navigator.sayswho= (function(){
    var ua= navigator.userAgent, tem, 
    M= ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || [];
    if(/trident/i.test(M[1])){
        tem=  /\brv[ :]+(\d+)/g.exec(ua) || [];
        return 'IE '+(tem[1] || '');
    }
    if(M[1]=== 'Chrome'){
        tem= ua.match(/\b(OPR|Edge)\/(\d+)/);
        if(tem!= null) return tem.slice(1).join(' ').replace('OPR', 'Opera');
    }
    M= M[2]? [M[1], M[2]]: [navigator.appName, navigator.appVersion, '-?'];
    if((tem= ua.match(/version\/(\d+)/i))!= null) M.splice(1, 1, tem[1]);
    return M.join(' ');
})();

console.log(navigator.sayswho); // outputs: `Chrome 62`

Keane

Answer 24

I use this to get de Name and number (int) of the version of the actual browser:

function getInfoBrowser() {
    var ua = navigator.userAgent, tem,
    M = ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || [];
    if (/trident/i.test(M[1])) {
        tem = /\brv[ :]+(\d+)/g.exec(ua) || [];
        return { name: 'Explorer', version: parseInt((tem[1] || '')) };
    }
    if (M[1] === 'Chrome') {
        tem = ua.match(/\b(OPR|Edge)\/(\d+)/);
        if (tem != null) { let app = tem.slice(1).toString().split(','); return { name: app[0].replace('OPR', 'Opera'), version: parseInt(app[1]) }; }
    }
    M = M[2] ? [M[1], M[2]] : [navigator.appName, navigator.appVersion, '-?'];
    if ((tem = ua.match(/version\/(\d+)/i)) != null) M.splice(1, 1, tem[1]);
    return {
        name: M[0],
        version: parseInt(M[1])
    };
}

function getBrowser(){
  let info = getInfoBrowser();
  $("#i-name").html(info.name);
  $("#i-version").html(info.version);
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<input type="button" onclick="getBrowser();" value="Get Info Browser"/>
<hr/>
Name: <span id="i-name"></span><br/>
Version: <span id="i-version"></span>

This run in

Chrome ; Firefox ; Safari ; Internet Explorer (>= 9) ; Opera ; Edge

For me.

Rimskykorsakov

Answer 25

For any PWA application using angular you can put the code to check if browser is supported or not in body section of index.html -

<body>
    <div id="browser"></div>
    <script>
        var operabrowser = true;
        operabrowser = (navigator.userAgent.indexOf('Opera Mini') > -1);
        if (operabrowser) {
            txt = "<p>Browser not supported use different browser...</p>";
            document.getElementById("browser").innerHTML = txt;
        }
    </script>
</body>

Allanite

Answer 26

Based on the accepted answer, this is an update for detecting "Microsoft Edge"

navigator.sayswho= (function(){
    var ua= navigator.userAgent;
    var tem; 
    var M= ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || [];
    if(/trident/i.test(M[1])){
        tem=  /\brv[ :]+(\d+)/g.exec(ua) || [];
        return 'IE '+(tem[1] || '');
    }
    if(M[1]=== 'Chrome'){
        tem= ua.match(/\b(OPR|Edg)\/(\d+)/);
        if(tem!= null) return tem.slice(1).join(' ').replace('OPR', 'Opera');
    }
    M= M[2]? [M[1], M[2]]: [navigator.appName, navigator.appVersion, '-?'];
    if((tem= ua.match(/version\/(\d+)/i))!= null) M.splice(1, 1, tem[1]);
    return M.join(' ');
})();

console.log(navigator.sayswho); 

Deviled

Do not rely on window.navigator.appVersion property to return the correct browser version. It is Deprecated – Outing

Answer 27

var ua = navigator.userAgent;

if (/Firefox\//.test(ua))
   var Firefox = /Firefox\/([0-9\.A-z]+)/.exec(ua)[1];

Schmitz

could use some clarity on whats going on. whats the input, whats the output. how does one use this. also i would put the if block into brackets for greater clarity. – Sisterinlaw

Answer 28

I wrote this for my needs.

It get info like if is a mobile device or if has a retina display

try it

var nav = {
        isMobile:function(){
            return (navigator.userAgent.match(/iPhone|iPad|iPod|Android|BlackBerry|Opera Mini|IEMobile/i) != null);
        },
        isDesktop:function(){
            return (navigator.userAgent.match(/iPhone|iPad|iPod|Android|BlackBerry|Opera Mini|IEMobile/i) == null);
        },
        isAndroid: function() {
            return navigator.userAgent.match(/Android/i);
        },
        isBlackBerry: function() {
            return navigator.userAgent.match(/BlackBerry/i);
        },
        isIOS: function() {
            return navigator.userAgent.match(/iPhone|iPad|iPod/i);
        },
        isOpera: function() {
            return navigator.userAgent.match(/Opera Mini/i);
        },
        isWindows: function() {
            return navigator.userAgent.match(/IEMobile/i);
        },
        isRetina:function(){
            return window.devicePixelRatio && window.devicePixelRatio > 1;
        },
        isIPad:function(){
            isIPad = (/ipad/gi).test(navigator.platform);
            return isIPad;
        },
        isLandscape:function(){
            if(window.innerHeight < window.innerWidth){
                return true;
            }
            return false;
        },
        getIOSVersion:function(){
            if(this.isIOS()){
                var OSVersion = navigator.appVersion.match(/OS (\d+_\d+)/i);
                OSVersion = OSVersion[1] ? +OSVersion[1].replace('_', '.') : 0;
                return OSVersion;
            }
            else
                return false;
        },
        isStandAlone:function(){
            if(_.is(navigator.standalone))
                return navigator.standalone;
            return false;
        },
        isChrome:function(){
            var isChrome = (/Chrome/gi).test(navigator.appVersion);
            var isSafari = (/Safari/gi).test(navigator.appVersion)
            return isChrome && isSafari;
        },
        isSafari:function(){
            var isSafari = (/Safari/gi).test(navigator.appVersion)
            var isChrome = (/Chrome/gi).test(navigator.appVersion)
            return !isChrome && isSafari;
        }
}

Blanco

Note: Do not rely on navigator.appVersion property to return the correct browser version. It is Deprecated – Outing

Answer 29

I use this piece of javascript code based on what I could find in another posts.

var browserHelper = function () {
    var self = {};

    /// IE 6+
    self.isIEBrowser = function () {
        return /*@cc_on!@*/false || !!document.documentMode;
    };

    /// Opera 8.0+
    self.isOperaBrowser = function () {
        return (!!window.opr && !!opr.addons)
            || !!window.opera
            || navigator.userAgent.indexOf(' OPR/') >= 0;
    };

    /// Firefox 1.0+
    self.isFirefoxBrowser = function () {
        return typeof InstallTrigger !== 'undefined';
    };

    /// Safari 3.0+
    self.isSafariBrowser = function () {
        return /constructor/i.test(window.HTMLElement)
            || (function (p) { return p.toString() === "[object SafariRemoteNotification]"; })(!window['safari'] || (typeof safari !== 'undefined' && window['safari'].pushNotification));
    };

    /// Edge 20+
    self.isEdgeBrowser = function () {
        return !self.isIEBrowser() && !!window.StyleMedia;
    };

    /// Chrome 1 - 87
    self.isChromeBrowser = function () {
        return (!!window.chrome && (!!window.chrome.webstore || !!window.chrome.runtime))
            || (navigator.userAgent.indexOf("Chrome") > -1) && !self.isOperaBrowser();
    };

    /// Edge (based on chromium)
    self.isEdgeChromiumBrowser = function () {
        return self.isChromeBrowser() && (navigator.userAgent.indexOf("Edg") != -1);
    };

    /// Blink
    self.isBlinkBasedOnBrowser = function () {
        return (self.isChromeBrowser() || self.isOperaBrowser()) && !!window.CSS;
    };

    /// Returns the name of the navigator
    self.browserName = function () {

        if (self.isOperaBrowser()) return "Opera";

        if (self.isEdgeBrowser()) return "Edge";

        if (self.isEdgeChromiumBrowser()) return "Edge (based on chromium)";

        if (self.isFirefoxBrowser()) return "Firefox";

        if (self.isIEBrowser()) return "Internet Explorer";

        if (self.isSafariBrowser()) return "Safari";

        if (self.isChromeBrowser()) return "Chrome";

        return "Unknown";
    };
    
    return self;
};

var bName = document.getElementById('browserName');
bName.innerText = browserHelper().browserName();

#browserName {
  font-family: Arial, Verdana;
  font-size: 1.2rem;
  color: #ff8000;
  text-align: center;
  border: 2px solid #ff8000;
  border-radius: .5rem;
  padding: .5rem;
  max-width: 25%;
  margin: auto;
}

<div id="browserName"></div>

Orlene

Answer 30

For chromium browser is so simple.

Version : navigator.userAgentData.brands[0].version

Browser Name : navigator.userAgentData.brands[0].brand

Obidiah

These are empty for me in Chromium. – Sherfield

Note that this is supported only since chromium 90 (developer.mozilla.org/en-US/docs/Web/API/Navigator/…) – Hamamatsu

Answer 31

This got me the version of Firefox,

    let versionNumber = parseInt(window.navigator.userAgent.match(/Firefox\/([0- 
    9]+)\./)[1]);

Commandant

Answer 32

Why not another one liner solution:

navigator.userAgent.includes("Firefox")? log("Mozilla") :log("Chrome")

Congressional

Answer 33

An updated code to detect browsers from iOS.

navigator.sayswho= (function(){
var ua= navigator.userAgent;
var tem; 
var M= ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || [];
if(/trident/i.test(M[1])){
    tem=  /\brv[ :]+(\d+)/g.exec(ua) || [];
    return 'IE '+(tem[1] || '');
}
if(M[1]=== 'Chrome'){
    tem= ua.match(/\b(OPR)\/(\d+)/);
    if(tem!= null) return 'Opera '+ tem.slice(1)[1];
    tem= ua.match(/\b(Edg[a-zA-Z]{0,3})\/(\d+)/);
    if(tem!= null) return 'Edge '+ tem.slice(1)[1];
} else if(M[1]=== 'Safari') {
    tem= ua.match(/\b(EdgiOS)\/(\d+)/);
    if(tem!= null) return 'Edge '+ tem.slice(1)[1];
    tem= ua.match(/\b(FxiOS)\/(\d+)/);
    if(tem!= null) return 'Firefox '+ tem.slice(1)[1];
    tem= ua.match(/\b(CriOS)\/(\d+)/);
    if(tem!= null) return 'Chrome '+ tem.slice(1)[1];
} 
M= M[2]? [M[1], M[2]]: [navigator.appName, navigator.appVersion, '-?'];
if((tem= ua.match(/version\/(\d+)/i))!= null) M.splice(1, 1, tem[1]);
return M.join(' ');

})();

Nairobi

Answer 34

var nVer = navigator.appVersion;
var nAgt = navigator.userAgent;
var browserName = navigator.appName;
var fullVersion = '' + parseFloat(navigator.appVersion);
var majorVersion = parseInt(navigator.appVersion, 10);
var nameOffset, verOffset, ix;

// In Opera 15+, the true version is after "OPR/" 
if ((verOffset = nAgt.indexOf("OPR/")) != -1) {
    browserName = "Opera";
    fullVersion = nAgt.substring(verOffset + 4);
}
// In older Opera, the true version is after "Opera" or after "Version"
else if ((verOffset = nAgt.indexOf("Opera")) != -1) {
    browserName = "Opera";
    fullVersion = nAgt.substring(verOffset + 6);
    if ((verOffset = nAgt.indexOf("Version")) != -1)
        fullVersion = nAgt.substring(verOffset + 8);
}
// In MSIE, the true version is after "MSIE" in userAgent
else if ((verOffset = nAgt.indexOf("MSIE")) != -1) {
    browserName = "Microsoft Internet Explorer";
    fullVersion = nAgt.substring(verOffset + 5);
}
// In Chrome, the true version is after "Chrome" 
else if ((verOffset = nAgt.indexOf("Chrome")) != -1) {
    browserName = "Google Chrome";
    fullVersion = nAgt.substring(verOffset + 7);
}
// In Safari, the true version is after "Safari" or after "Version" 
else if ((verOffset = nAgt.indexOf("Safari")) != -1) {
    browserName = "Safari";
    fullVersion = nAgt.substring(verOffset + 7);
    if ((verOffset = nAgt.indexOf("Version")) != -1)
        fullVersion = nAgt.substring(verOffset + 8);
}
// In Firefox, the true version is after "Firefox" 
else if ((verOffset = nAgt.indexOf("Firefox")) != -1) {
    browserName = "Mozilla Firefox";
    fullVersion = nAgt.substring(verOffset + 8);
}
// In most other browsers, "name/version" is at the end of userAgent 
else if ((nameOffset = nAgt.lastIndexOf(' ') + 1) < (verOffset = nAgt.lastIndexOf('/'))) {
    browserName = nAgt.substring(nameOffset, verOffset);
    fullVersion = nAgt.substring(verOffset + 1);
    if (browserName.toLowerCase() == browserName.toUpperCase()) {
        browserName = navigator.appName;
    }
}
// trim the fullVersion string at semicolon/space if present
if ((ix = fullVersion.indexOf(';')) != -1) fullVersion = fullVersion.substring(0, ix);
if ((ix = fullVersion.indexOf(' ')) != -1) fullVersion = fullVersion.substring(0, ix);

majorVersion = parseInt('' + fullVersion, 10);
if (isNaN(majorVersion)) {
    fullVersion = '' + parseFloat(navigator.appVersion);
    majorVersion = parseInt(navigator.appVersion, 10);
}

Cowpea

Can you please put some description of your code along with the code? – Basicity