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 (!$var)7 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms7 ms4772
if (empty($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 ms411
if ('' == $var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms460
if ($var === '')>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms343
if ('' === $var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms348
if (strcmp($var, '') == 0)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms591
if (strcmp('', $var) == 0)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms594
if (strlen($var) == 0)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms381
if (!strlen($var))>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms381

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($array) === 0 //by reference>0 ms>0 ms>0 ms220
count($array) === 0 //by value>0 ms>0 ms>0 ms178
$array === []>0 ms>0 ms>0 ms104
empty($array)>0 ms>0 ms>0 ms100
(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 ms194
$a === $b>0 ms>0 ms>0 ms>0 ms100
!strcmp($a, $b)>0 ms>0 ms>0 ms1 ms356
strcmp($a, $b) == 0>0 ms>0 ms>0 ms1 ms420
strcmp($a, $b) === 0>0 ms>0 ms>0 ms1 ms385
strcasecmp($a, $b) === 0>0 ms>0 ms1 ms1 ms732

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, $needle)>0 ms>0 ms>0 ms>0 ms>0 ms155
strpos($haystack, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms100
strstr($haystack, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms154
stristr($haystack, $needle)3 ms3 ms3 ms3 ms10 ms7170
preg_match("/$needle/", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms782
preg_match("/$needle/i", $haystack)1 ms>0 ms>0 ms1 ms1 ms912
preg_match("/$needle/S", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms753

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
$haystack[0] === 'n'>0 ms>0 ms>0 ms>0 ms>0 ms123
strncmp($haystack, $needle, strlen($needle)) === 0>0 ms>0 ms>0 ms>0 ms>0 ms123
strncmp($haystack, 'needle', 6) === 0>0 ms>0 ms>0 ms>0 ms>0 ms119
strncasecmp($haystack, $needle, strlen($needle)) === 0>0 ms>0 ms>0 ms>0 ms>0 ms115
strpos($haystack, $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms292
substr($haystack, 0, strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms100
strcmp(substr($haystack, 0, strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms183
substr_compare($haystack, $needle, 0, strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms171
substr_compare($haystack, $needle, 0)>0 ms>0 ms>0 ms>0 ms>0 ms147
preg_match('/^' . preg_quote($needle, '/') . '/', $haystack)>0 ms>0 ms>0 ms>0 ms>0 ms530

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 ms160
substr($haystack, strlen($haystack) - strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms142
substr($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 ms100
strcmp(substr($haystack, -strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms270
substr_compare($haystack, $needle, -strlen($needle), strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms250
substr_compare($haystack, $needle, -strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms214
preg_match('/' . preg_quote($needle, '/') . '$/', $haystack)>0 ms>0 ms>0 ms>0 ms1 ms5228

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, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms120
preg_replace("/$search/", $replace, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms257
preg_replace("/$search/S", $replace, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms246
strtr($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, $subject)>0 ms>0 ms>0 ms>0 ms1 ms123
strtr($subject, $fromChar, $toChar)1 ms3 ms2 ms1 ms7 ms1636
strtr($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($string, ',')>0 ms>0 ms>0 ms>0 ms>0 ms100
preg_replace('/^,*|,*$/', '', $string)>0 ms>0 ms>0 ms>0 ms1 ms3843
preg_replace('/^,*|,*$/m', '', $string)1 ms2 ms2 ms2 ms6 ms26838
preg_replace('/^,+|,+$/', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms561
preg_replace('/^,+|,+$/m', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms566
preg_replace('/^,+/', '', preg_replace('/,+$/', '', …))>0 ms>0 ms>0 ms>0 ms>0 ms811

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 ms176
preg_match_all('/[^,]+/', $string, $matches)>0 ms>0 ms1 ms2 ms269

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); $i++) //by reference>0 ms219
for ($i = 0; $i < count($array); $i++) //by value>0 ms197
for ($i = 0, $count = count($array); $i < $count; $i++)>0 ms100
for ($i = count($array) - 1; $i >= 0; $i--)>0 ms123
for ($i = count($array) - 1; $i >= 0; --$i)>0 ms123
$i = count($array); while ($i--)>0 ms146

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 ms101
$array['key']2 ms100

My conclusion: I like associative arrays.

Implode an Array

Method Summary Index
implode(' ', $array)>0 ms102
"$array[0] $array[1] $array[2]">0 ms102
$array[0] . ' ' . $array[1] . ' ' . $array[2]>0 ms100
sprintf('%s %s %s', $array[0], $array[1], $array[2])1 ms1897
vsprintf('%s %s %s', $array)1 ms2181

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

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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