Subtract time in PHP

Question

I have been looking for an answer for a few hours now, but I can't find one.

I'm writing a simple script. The user sets their work start and end time. So, for example, somebody is working from 8:00 to 16:00. How can I subtract this time to see how long the person has been working?

I was experimenting with strtotime(); but without success...

Centric

Answer 1

A bit nicer is the following:

$a = new DateTime('08:00');
$b = new DateTime('16:00');
$interval = $a->diff($b);

echo $interval->format("%H");

That will give you the difference in hours.

Cysto

I wonder if it can convert the entire interval into seconds? ->format('%S') just gave me the seconds part of the interval output, not the total calculated seconds elapsed. – Stockholder

Answer 2

If you get valid date strings, you can use this:

$workingHours = (strtotime($end) - strtotime($start)) / 3600;

This will give you the hours a person has been working.

Phaedrus

You can divide by 60 instead of 3600 to get minutes and divide by 60 and round down (floor()) to get full hours and get the remainder of minutes%60 to get the minutes. – Phaedrus

date ( 'H:i' , $workingHours ). I would not recommend strtottime here as strtotime gives you back the unix timestamp of a date. – Bourgeoisie

Answer 3

Another solution would be to go through the Unix-timestamp integer value difference (in seconds).

<?php
    $start = strtotime('10-09-2019 12:01:00');
      $end = strtotime('12-09-2019 13:16:00');

      $hours = intval(($end - $start)/3600);
      echo $hours.' hours'; //in hours

      //If you want it in minutes, you can divide the difference by 60 instead
      $mins = (int)(($end - $start) / 60);
      echo $mins.' minutues'.'<br>';
?>

This solution would be a better one if your original dates are stored in Unix-timestamp format.

Pleasurable

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