Last Updated: December 30, 2016
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17.78K
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PHP for() VS foreach() benchmark

Got curious what the performance difference between using for() and foreach() was on an array of elements in PHP. So, coded up a quick test.

GitHub Gist
https://gist.github.com/3909074/628478c74d736854f4499fa3383eb97e5db84b6f

<?php
    $elements = array();

    ////
    // An array of 10,000 elements with random string values
    ////
    for($i = 0; $i < 10000; $i++) {
            $elements[] = (string)rand(10000000, 99999999);
    }

    $time_start = microtime(true);

    ////
    // for test
    ////
    for($i = 0; $i < count($elements); $i++) { }

    $time_end = microtime(true);
    $for_time = $time_end - $time_start;

    $time_start = microtime(true);

    ////
    // foreach test
    ////
    foreach($elements as $element) { }

    $time_end = microtime(true);
    $foreach_time = $time_end - $time_start;

    echo "For took: " . number_format($for_time * 1000, 3) . "ms\n";
    echo "Foreach took: " . number_format($foreach_time * 1000, 3) . "ms\n";
?>

The result in PHP 5.3.15 with Suhosin-Patch (cli) (built: Aug 24 2012 17:45:44) on a MacBook Pro.

For took: 1.612ms
Foreach took: 0.602ms

Here is the result in PHP 5.4.7 (cli) (built: Sep 17 2012 21:16:51) on a virtual machine in SoftLayer with two CPUs and 1GB of RAM.

For took: 1.836ms
Foreach took: 0.543ms

--- UPDATE ---

Here is an updated GitHub Gist which also includes the time to execute for() without calling count() on each iteration. It is the fastest of all three methods.

https://gist.github.com/3909074

5 Responses
Add your response

Why are you counting elements in an array before every iteration?
Shouldn't it be a better solution?

$elementscount = count($elements);
for($i = 0; $i < $elements
count; $i++) { }

I can be almost sure that now the results will be slightly different!

over 1 year ago ·

Sorry, didn't spot the update at the bottom ;)

over 1 year ago ·

U suck. Don't use count() func in every iteration, noob!
Then For fastest Foreach; Just use count() before for!

over 1 year ago ·

@sergeyaleynicov Way to be a douche.

over 1 year ago ·

If u can just use count() before for! Then For fastest Foreach hahaha. core wrong !

over 1 year ago ·