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 (!$var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms421
if (empty($var))>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms100
if ($var == '')>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms559
if ('' == $var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms544
if ($var === '')>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms420
if ('' === $var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms460
if (strcmp($var, '') == 0)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms1372
if (strcmp('', $var) == 0)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms2 ms1478
if (strlen($var) == 0)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms506
if (!strlen($var))>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms553

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($array) === 0 //by reference>0 ms>0 ms>0 ms155
count($array) === 0 //by value>0 ms>0 ms>0 ms150
$array === []>0 ms>0 ms>0 ms100
empty($array)>0 ms>0 ms>0 ms103
(bool)$array>0 ms>0 ms>0 ms179

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 ms>0 ms193
$a === $b>0 ms>0 ms>0 ms>0 ms100
!strcmp($a, $b)1 ms1 ms1 ms2 ms1286
strcmp($a, $b) == 01 ms1 ms1 ms2 ms1264
strcmp($a, $b) === 01 ms1 ms1 ms2 ms1515
strcasecmp($a, $b) === 01 ms1 ms1 ms3 ms1766

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, $needle)>0 ms>0 ms>0 ms>0 ms>0 ms164
strpos($haystack, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms100
strstr($haystack, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms175
stristr($haystack, $needle)2 ms2 ms2 ms2 ms9 ms5741
preg_match("/$needle/", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms414
preg_match("/$needle/i", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms454
preg_match("/$needle/S", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms345

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 ms324
strncmp($haystack, 'needle', 6) === 0>0 ms>0 ms>0 ms>0 ms>0 ms369
strncasecmp($haystack, $needle, strlen($needle)) === 0>0 ms>0 ms>0 ms>0 ms>0 ms306
strpos($haystack, $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms485
substr($haystack, 0, strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms275
strcmp(substr($haystack, 0, strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms607
substr_compare($haystack, $needle, 0, strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms331
substr_compare($haystack, $needle, 0)>0 ms>0 ms>0 ms>0 ms>0 ms318
preg_match('/^' . preg_quote($needle, '/') . '/', $haystack)>0 ms>0 ms>0 ms>0 ms>0 ms922

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)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms218
substr($haystack, -strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms268
substr($haystack, -1) === 'n'>0 ms>0 ms>0 ms>0 ms>0 ms172
strcmp(substr($haystack, -strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms362
substr_compare($haystack, $needle, -strlen($needle), strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms241
substr_compare($haystack, $needle, -strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms216
preg_match('/' . preg_quote($needle, '/') . '$/', $haystack)>0 ms>0 ms>0 ms>0 ms1 ms1830

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, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms177
preg_replace("/$search/", $replace, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms257
preg_replace("/$search/S", $replace, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms249
strtr($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, $subject)>0 ms>0 ms>0 ms>0 ms1 ms168
strtr($subject, $fromChar, $toChar)1 ms2 ms2 ms1 ms7 ms1583
strtr($subject, array($fromChar => $toChar))>0 ms>0 ms>0 ms>0 ms>0 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($string, ',')>0 ms>0 ms>0 ms>0 ms>0 ms100
preg_replace('/^,*|,*$/', '', $string)>0 ms>0 ms>0 ms>0 ms1 ms929
preg_replace('/^,*|,*$/m', '', $string)2 ms1 ms2 ms2 ms6 ms6778
preg_replace('/^,+|,+$/', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms203
preg_replace('/^,+|,+$/m', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms166
preg_replace('/^,+/', '', preg_replace('/,+$/', '', …))>0 ms>0 ms>0 ms>0 ms>0 ms325

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 ms1 ms1 ms196
preg_match_all('/[^,]+/', $string, $matches)>0 ms>0 ms1 ms2 ms252

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); $i++) //by reference>0 ms280
for ($i = 0; $i < count($array); $i++) //by value>0 ms221
for ($i = 0, $count = count($array); $i < $count; $i++)>0 ms100
for ($i = count($array) - 1; $i >= 0; $i--)>0 ms126
for ($i = count($array) - 1; $i >= 0; --$i)>0 ms120
$i = count($array); while ($i--)>0 ms150

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]2 ms100
$array['key']2 ms115

My conclusion: I like associative arrays.

Implode an Array

Method Summary Index
implode(' ', $array)1 ms1999
"$array[0] $array[1] $array[2]">0 ms100
$array[0] . ' ' . $array[1] . ' ' . $array[2]>0 ms119
sprintf('%s %s %s', $array[0], $array[1], $array[2])1 ms2689
vsprintf('%s %s %s', $array)2 ms3340

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 ms126
"contains no dollar signs">0 ms100
'$variables $are $not $replaced'>0 ms120
"\$variables \$are \$not \$replaced">0 ms106
"$variables $are $replaced">0 ms124
$variables . ' ' . $are . ' ' . $replaced>0 ms116
$variables . " " . $are . " " . $replaced>0 ms159

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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