Just wrote up some test cases in jsperf to test the difference between named and anonymous functions while using Array.map and other alternatives. http://jsperf.com/map-reduce-named-functions (ex...

What is the fastest method, to add a new value at the beginning of a string?

I want to remove the sign of a Number in JavaScript. Here are the test cases that I already examined at jsperf if(n < 0) n *= -1; if(n < 0) n = -n; n = Math.abs(n) (n < 0) && (n...

I created a benchmark on both jsperf.com and jsben.ch, however, they're giving substantially different results. JSPerf: https://jsperf.com/join-vs-template-venryx JSBench: http://jsben.ch/9DaxR N...

Which is the best way to resume the value of an array into simple true or false values. I am quite confused as jsperf is giving me VERY different results than what google chrome console, nodejs, o...

I don't trust results from jsperf measuring performance of for loop vs forEach. At least for chrome and firefox on my machine results are completely different than the ones being advertised in jspe...

I am measuring my website's performance on the basis of performance object provided by HTML5 and I want to know that what is going wrong with my application, I also want to log these performance ob...

I am seeing some odd behavior in a jsperf test. Here is the setup: var pro={}; pro._x=3; var q=Object.create(pro); q.x=3; q.z={}; q.z.x=3; Then I simply lookup each of the properties q.x, q._x, ...

I was playing around with jQuery's .text() and .html() methods and running some simple jsPerf tests, when I was startled to discover that .html() is nearly a magnitude faster at retrieving text: ...

First of all, I made a quick jsperf test case to show the obvious : Object.create(null) is way slower than creating a object with the {} syntax. http://jsperf.com/js-object-creation-null-proto But...

If I do the following: var abs = Math.abs; Shoudn't abs(-10) be faster than Math.abs(-10)? Because abs is called directly. This is what called my attention: Math.abs vs custom abs function Updat...

I tested the differences between 2 ID selectors, the first is normal : $('#lol') And the second is the same but placed between multiple parenthesis : $((((('#lol'))))) I launched a test on jsperf,...

I'm doing my first steps with jsperf (here) to improve the performance of some of my scripts. I'm wondering if it is possible to delete/remove test revisions, which I have accidentially published ...

I've been looking at the source code of my.class.js to find out what makes it so fast on Firefox. Here's the snippet of code used to create a class: my.Class = function () { var len = argum...

Can anyone may explain me why creating object via string is slower than same object and execute addClass() method in jQuery? I thought that addClass() method will be slower, but it is not. I'm won...

I started a series of posts on javascript / jQuery optimization and stumbled upon this interesting result. Why is it that minimizing jQuery objects (by searching from a cached jQuery collection) ...

The Benchmark: http://jsperf.com/substringing So, I'm starting up my very first HTML5 browser-based client-side project. It's going to have to parse very, very large text files into, essentially, a...

I ran a test on this website http://jsperf.com/ I want some one to explain What does green and pink signifies What is ops per second what is 95,814,583 what is +- 1.95% is whats does 'fastest...

Today I visited jsPerf and now I am wondering… What is "ops/sec"? How many iterations does it do? On what basis does it calculate which is faster? What is the formula behind these calcul...

I ran a simple jsperf test and everything went as expected when running in Firefox but when I ran the test in Google Chrome is was confused. The test is testing different ways of declaring functi...