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 (!$var)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms416
if (empty($var))>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms100
if ($var == '')1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms537
if ('' == $var)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms527
if ($var === '')1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms430
if ('' === $var)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms437
if (strcmp($var, '') == 0)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms2 ms1092
if (strcmp('', $var) == 0)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms2 ms1141
if (strlen($var) == 0)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms495
if (!strlen($var))1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms468

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($array) === 0 //by reference>0 ms>0 ms>0 ms247
count($array) === 0 //by value>0 ms>0 ms>0 ms195
$array === []>0 ms>0 ms>0 ms100
empty($array)>0 ms>0 ms>0 ms104
(bool)$array>0 ms>0 ms>0 ms221

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 ms271
$a === $b>0 ms>0 ms>0 ms>0 ms100
!strcmp($a, $b)1 ms1 ms1 ms2 ms1257
strcmp($a, $b) == 01 ms1 ms1 ms2 ms1265
strcmp($a, $b) === 01 ms1 ms1 ms2 ms1268
strcasecmp($a, $b) === 01 ms1 ms2 ms3 ms1666

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, $needle)>0 ms>0 ms>0 ms>0 ms>0 ms163
strpos($haystack, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms100
strstr($haystack, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms159
stristr($haystack, $needle)3 ms2 ms2 ms2 ms9 ms3419
preg_match("/$needle/", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms220
preg_match("/$needle/i", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms259
preg_match("/$needle/S", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms367

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 ms212
strncmp($haystack, 'needle', 6) === 0>0 ms>0 ms>0 ms>0 ms>0 ms210
strncasecmp($haystack, $needle, strlen($needle)) === 0>0 ms>0 ms>0 ms>0 ms>0 ms190
strpos($haystack, $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms548
substr($haystack, 0, strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms297
strcmp(substr($haystack, 0, strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms369
substr_compare($haystack, $needle, 0, strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms212
substr_compare($haystack, $needle, 0)>0 ms>0 ms>0 ms>0 ms>0 ms196
preg_match('/^' . preg_quote($needle, '/') . '/', $haystack)>0 ms>0 ms>0 ms>0 ms1 ms1048

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)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms205
substr($haystack, -strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms139
substr($haystack, -1) === 'n'>0 ms>0 ms>0 ms>0 ms>0 ms127
strcmp(substr($haystack, -strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms268
substr_compare($haystack, $needle, -strlen($needle), strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms170
substr_compare($haystack, $needle, -strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms161
preg_match('/' . preg_quote($needle, '/') . '$/', $haystack)>0 ms>0 ms>0 ms>0 ms1 ms1606

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, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms156
preg_replace("/$search/", $replace, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms240
preg_replace("/$search/S", $replace, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms226
strtr($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, $subject)>0 ms>0 ms>0 ms>0 ms1 ms135
strtr($subject, $fromChar, $toChar)1 ms2 ms2 ms1 ms7 ms1513
strtr($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($string, ',')>0 ms>0 ms>0 ms>0 ms>0 ms100
preg_replace('/^,*|,*$/', '', $string)>0 ms>0 ms>0 ms>0 ms1 ms958
preg_replace('/^,*|,*$/m', '', $string)2 ms1 ms1 ms1 ms6 ms6490
preg_replace('/^,+|,+$/', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms217
preg_replace('/^,+|,+$/m', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms156
preg_replace('/^,+/', '', preg_replace('/,+$/', '', …))>0 ms>0 ms>0 ms>0 ms>0 ms288

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 ms174
preg_match_all('/[^,]+/', $string, $matches)>0 ms>0 ms1 ms2 ms262

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); $i++) //by reference>0 ms291
for ($i = 0; $i < count($array); $i++) //by value>0 ms224
for ($i = 0, $count = count($array); $i < $count; $i++)>0 ms100
for ($i = count($array) - 1; $i >= 0; $i--)>0 ms115
for ($i = count($array) - 1; $i >= 0; --$i)>0 ms123
$i = count($array); while ($i--)>0 ms142

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]3 ms119
$array['key']2 ms100

My conclusion: I like associative arrays.

Implode an Array

Method Summary Index
implode(' ', $array)1 ms1964
"$array[0] $array[1] $array[2]">0 ms100
$array[0] . ' ' . $array[1] . ' ' . $array[2]>0 ms107
sprintf('%s %s %s', $array[0], $array[1], $array[2])2 ms2755
vsprintf('%s %s %s', $array)1 ms2629

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 ms102
"contains no dollar signs">0 ms100
'$variables $are $not $replaced'>0 ms118
"\$variables \$are \$not \$replaced">0 ms102
"$variables $are $replaced">0 ms129
$variables . ' ' . $are . ' ' . $replaced>0 ms124
$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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