My PHP Performance Benchmarks

PHP version 7.4.33 is running on this server. The benchmarks are done live. Reload the page to get fresh numbers. You are free to use the source for whatever you want. Giving credits to me (Thiemo Mättig) would be nice.

Please note that these are micro benchmarks. Micro benchmarks are stupid. I created this comparison to learn something about PHP and how the PHP compiler works. This can not be used to compare PHP versions or servers.

Check if a String is empty

Method Undefined Null False Empty string String '0' String '1' Long string Summary Index
if (!$var)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms369
if (empty($var))>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms100
if ($var == '')12 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms13 ms7540
if ('' == $var)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms462
if ($var === '')>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms298
if ('' === $var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms357
if (strcmp($var, '') == 0)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms2 ms1173
if (strcmp('', $var) == 0)1 ms>0 ms>0 ms>0 ms>0 ms4 ms>0 ms6 ms3607
if (strlen($var) == 0)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms409
if (!strlen($var))>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms359

My conclusion: In most cases, Do not use empty() because it does not trigger a warning when used with undefined variables. Note that empty('0') returns true. Use strlen() if you want to detect '0'. Try to avoid == at all because it may cause strange behaviour (e.g. '9a' == 9 returns true). Prefer === over == and !== over != if possible because it does compare the variable types in addition to the contents.

Check if an Array is empty

Method Empty array 100 elements Summary Index
count($array) === 0 //by reference>0 ms>0 ms>0 ms256
count($array) === 0 //by value>0 ms>0 ms>0 ms193
$array === []>0 ms>0 ms>0 ms112
empty($array)>0 ms>0 ms>0 ms100
(bool)$array>0 ms>0 ms>0 ms225

My conclusion: Why count if you don't care about the exact number?

Compare two Strings

Method Equal First character not equal Last character not equal Summary Index
$a == $b>0 ms>0 ms>0 ms1 ms318
$a === $b>0 ms>0 ms>0 ms>0 ms100
!strcmp($a, $b)1 ms1 ms1 ms3 ms1426
strcmp($a, $b) == 01 ms1 ms7 ms9 ms4454
strcmp($a, $b) === 01 ms1 ms1 ms3 ms1538
strcasecmp($a, $b) === 01 ms1 ms2 ms4 ms1878

My conclusion: Use what fits your needs.

Check if a String contains another String

Method Not found Found at the start Found in the middle Found at the end Summary Index
strstr($haystack, $needle)>0 ms>0 ms>0 ms>0 ms>0 ms178
strpos($haystack, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms100
strstr($haystack, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms163
stristr($haystack, $needle)5 ms17 ms3 ms3 ms28 ms10846
preg_match("/$needle/", $haystack)1 ms>0 ms>0 ms>0 ms1 ms461
preg_match("/$needle/i", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms394
preg_match("/$needle/S", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms377

My conclusion: It does not matter if you use strstr() or strpos(). Use the preg…() functions only if you need the power of regular expressions. Never use the ereg…() functions.

Check if a String starts with another String

Method Not found Found at the start Found in the middle Found at the end Summary Index
$haystack[0] === 'n'>0 ms>0 ms>0 ms>0 ms>0 ms100
strncmp($haystack, $needle, strlen($needle)) === 0>0 ms>0 ms>0 ms>0 ms>0 ms152
strncmp($haystack, 'needle', 6) === 0>0 ms>0 ms>0 ms>0 ms>0 ms139
strncasecmp($haystack, $needle, strlen($needle)) === 0>0 ms>0 ms>0 ms>0 ms>0 ms145
strpos($haystack, $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms260
substr($haystack, 0, strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms157
strcmp(substr($haystack, 0, strlen($needle)), $needle) === 0>0 ms>0 ms7 ms>0 ms7 ms8606
substr_compare($haystack, $needle, 0, strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms166
substr_compare($haystack, $needle, 0)>0 ms>0 ms>0 ms>0 ms>0 ms120
preg_match('/^' . preg_quote($needle, '/') . '/', $haystack)>0 ms>0 ms>0 ms>0 ms>0 ms493

My conclusion: strpos() is very fast and can be used in almost all cases. strncmp() is good if you are looking for a constant length needle.

Check if a String ends with another String

Method Not found Found at the start Found in the middle Found at the end Summary Index
$haystack[strlen($haystack) - 1] === 'n'>0 ms>0 ms>0 ms>0 ms>0 ms100
substr($haystack, strlen($haystack) - strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms144
substr($haystack, -strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms138
substr($haystack, -1) === 'n'>0 ms>0 ms>0 ms>0 ms>0 ms155
strcmp(substr($haystack, -strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms291
substr_compare($haystack, $needle, -strlen($needle), strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms187
substr_compare($haystack, $needle, -strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms172
preg_match('/' . preg_quote($needle, '/') . '$/', $haystack)>0 ms>0 ms>0 ms>0 ms2 ms2000

My conclusion: Using substr() with a negative position is a good trick.

Replace a (>1 Character) String inside another String

Method Not found Found at the start Found in the middle Found at the end Summary Index
str_replace($search, $replace, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms181
preg_replace("/$search/", $replace, $subject)>0 ms1 ms>0 ms>0 ms2 ms855
preg_replace("/$search/S", $replace, $subject)>0 ms>0 ms>0 ms>0 ms1 ms248
strtr($subject, array($search => $replace))>0 ms>0 ms>0 ms>0 ms>0 ms100

My conclusion: Never use the ereg…() functions.

Replace a Character inside a String

Method Not found Found at the start Found in the middle Found at the end Summary Index
str_replace($fromChar, $toChar, $subject)>0 ms>0 ms>0 ms>0 ms1 ms114
strtr($subject, $fromChar, $toChar)3 ms3 ms19 ms2 ms28 ms2790
strtr($subject, array($fromChar => $toChar))>0 ms>0 ms>0 ms>0 ms1 ms100

My conclusion: Since PHP 7.0 strtr() can sometimes beat str_replace().

Trim Characters from the Beginning and End of a String

Method Not found Found at start Found at end Found at both sides Summary Index
trim($string, ',')>0 ms>0 ms>0 ms>0 ms>0 ms100
preg_replace('/^,*|,*$/', '', $string)>0 ms>0 ms>0 ms>0 ms1 ms825
preg_replace('/^,*|,*$/m', '', $string)3 ms41 ms2 ms3 ms49 ms32538
preg_replace('/^,+|,+$/', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms257
preg_replace('/^,+|,+$/m', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms150
preg_replace('/^,+/', '', preg_replace('/,+$/', '', …))>0 ms>0 ms>0 ms>0 ms>0 ms318

My conclusion: Always benchmark your regular expressions! In this case, with .* you also replace nothing with nothing which takes time because there is a lot of “nothing” in every string.

Split a String into an Array

Method Empty string Single occurrence Multiple occurrences Summary Index
explode(',', $string)>0 ms>0 ms1 ms1 ms100
preg_split('/,/', $string)>0 ms>0 ms2 ms2 ms153
preg_match_all('/[^,]+/', $string, $matches)>0 ms>0 ms3 ms4 ms246

My conclusion: Don't use split(). It got deprecated in PHP 5.3 and removed from PHP 7.0.

Loop a numerical indexed Array of Strings

Method Summary Index
for ($i = 0; $i < count($array); $i++) //by reference>0 ms282
for ($i = 0; $i < count($array); $i++) //by value>0 ms259
for ($i = 0, $count = count($array); $i < $count; $i++)>0 ms100
for ($i = count($array) - 1; $i >= 0; $i--)>0 ms120
for ($i = count($array) - 1; $i >= 0; --$i)>0 ms217
$i = count($array); while ($i--)>0 ms182

My conclusion: count() could have been horribly slow in PHP 5 and below when copy-on-write accidentally kicked in. Always precalculate it, if possible.

Get Elements from an Array

Method Summary Index
$array[0]6 ms100
$array['key']8 ms144

My conclusion: I like associative arrays.

Implode an Array

Method Summary Index
implode(' ', $array)1 ms2333
"$array[0] $array[1] $array[2]">0 ms103
$array[0] . ' ' . $array[1] . ' ' . $array[2]>0 ms100
sprintf('%s %s %s', $array[0], $array[1], $array[2])2 ms2833
vsprintf('%s %s %s', $array)3 ms4721

My conclusion: String concatenation is a cheap operation in PHP. Don't waste your time benchmarking this.

The single vs. double Quotes Myth

Method Summary Index
'contains no dollar signs'>0 ms100
"contains no dollar signs">0 ms127
'$variables $are $not $replaced'>0 ms111
"\$variables \$are \$not \$replaced">0 ms138
"$variables $are $replaced">0 ms152
$variables . ' ' . $are . ' ' . $replaced>0 ms127
$variables . " " . $are . " " . $replaced>0 ms109

My conclusion: It does not matter if you use single or double quotes at all. The inclusion of variables has a measurable effect, but that's independent from the quotes.

© Thiemo Mättig, created in September 2008, updated in August 2017
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