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 (!$var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms519
if (empty($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 ms596
if ('' == $var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms617
if ($var === '')>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms584
if ('' === $var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms487
if (strcmp($var, '') == 0)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms1412
if (strcmp('', $var) == 0)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms2 ms1587
if (strlen($var) == 0)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms623
if (!strlen($var))>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms510

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($array) === 0 //by reference>0 ms>0 ms>0 ms221
count($array) === 0 //by value>0 ms>0 ms>0 ms295
$array === []>0 ms>0 ms>0 ms100
empty($array)>0 ms>0 ms>0 ms100
(bool)$array>0 ms>0 ms>0 ms163

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 ms222
$a === $b>0 ms>0 ms>0 ms>0 ms100
!strcmp($a, $b)1 ms1 ms1 ms2 ms1408
strcmp($a, $b) == 01 ms1 ms1 ms2 ms1482
strcmp($a, $b) === 01 ms1 ms1 ms2 ms1480
strcasecmp($a, $b) === 01 ms1 ms1 ms2 ms1826

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, $needle)>0 ms2 ms>0 ms>0 ms2 ms862
strpos($haystack, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms100
strstr($haystack, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms134
stristr($haystack, $needle)3 ms2 ms2 ms4 ms11 ms4927
preg_match("/$needle/", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms275
preg_match("/$needle/i", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms321
preg_match("/$needle/S", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms256

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 ms300
strncmp($haystack, 'needle', 6) === 0>0 ms>0 ms>0 ms>0 ms>0 ms242
strncasecmp($haystack, $needle, strlen($needle)) === 0>0 ms>0 ms>0 ms>0 ms>0 ms244
strpos($haystack, $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms394
substr($haystack, 0, strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms237
strcmp(substr($haystack, 0, strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms423
substr_compare($haystack, $needle, 0, strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms310
substr_compare($haystack, $needle, 0)>0 ms>0 ms>0 ms>0 ms>0 ms249
preg_match('/^' . preg_quote($needle, '/') . '/', $haystack)>0 ms>0 ms>0 ms>0 ms>0 ms818

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)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms207
substr($haystack, -strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms212
substr($haystack, -1) === 'n'>0 ms>0 ms>0 ms>0 ms>0 ms181
strcmp(substr($haystack, -strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms393
substr_compare($haystack, $needle, -strlen($needle), strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms243
substr_compare($haystack, $needle, -strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms237
preg_match('/' . preg_quote($needle, '/') . '$/', $haystack)>0 ms>0 ms>0 ms>0 ms1 ms2110

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, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms108
preg_replace("/$search/", $replace, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms173
preg_replace("/$search/S", $replace, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms203
strtr($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, $subject)>0 ms>0 ms>0 ms>0 ms1 ms100
strtr($subject, $fromChar, $toChar)1 ms3 ms2 ms2 ms9 ms1382
strtr($subject, array($fromChar => $toChar))>0 ms>0 ms>0 ms>0 ms1 ms105

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($string, ',')>0 ms>0 ms>0 ms>0 ms>0 ms100
preg_replace('/^,*|,*$/', '', $string)>0 ms>0 ms>0 ms>0 ms1 ms1081
preg_replace('/^,*|,*$/m', '', $string)2 ms2 ms2 ms2 ms8 ms7242
preg_replace('/^,+|,+$/', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms201
preg_replace('/^,+|,+$/m', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms186
preg_replace('/^,+/', '', preg_replace('/,+$/', '', …))>0 ms>0 ms>0 ms>0 ms>0 ms286

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 ms3 ms298
preg_match_all('/[^,]+/', $string, $matches)>0 ms1 ms1 ms2 ms248

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); $i++) //by reference>0 ms297
for ($i = 0; $i < count($array); $i++) //by value>0 ms206
for ($i = 0, $count = count($array); $i < $count; $i++)>0 ms100
for ($i = count($array) - 1; $i >= 0; $i--)>0 ms119
for ($i = count($array) - 1; $i >= 0; --$i)>0 ms119
$i = count($array); while ($i--)>0 ms141

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 ms101

My conclusion: I like associative arrays.

Implode an Array

Method Summary Index
implode(' ', $array)1 ms2170
"$array[0] $array[1] $array[2]">0 ms100
$array[0] . ' ' . $array[1] . ' ' . $array[2]>0 ms104
sprintf('%s %s %s', $array[0], $array[1], $array[2])1 ms2947
vsprintf('%s %s %s', $array)2 ms5239

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 ms115
'$variables $are $not $replaced'>0 ms117
"\$variables \$are \$not \$replaced">0 ms100
"$variables $are $replaced">0 ms102
$variables . ' ' . $are . ' ' . $replaced>0 ms132
$variables . " " . $are . " " . $replaced>0 ms100

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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