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 (!$var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms381
if (empty($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 ms498
if ('' == $var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms483
if ($var === '')>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms397
if ('' === $var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms403
if (strcmp($var, '') == 0)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms1135
if (strcmp('', $var) == 0)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms2 ms1303
if (strlen($var) == 0)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms700
if (!strlen($var))1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms620

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($array) === 0 //by reference>0 ms>0 ms>0 ms279
count($array) === 0 //by value>0 ms>0 ms>0 ms166
$array === []>0 ms>0 ms>0 ms105
empty($array)>0 ms>0 ms>0 ms100
(bool)$array>0 ms>0 ms>0 ms171

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 ms225
$a === $b>0 ms>0 ms>0 ms>0 ms100
!strcmp($a, $b)1 ms1 ms1 ms2 ms1250
strcmp($a, $b) == 01 ms1 ms1 ms2 ms1238
strcmp($a, $b) === 01 ms1 ms1 ms3 ms1702
strcasecmp($a, $b) === 01 ms1 ms2 ms4 ms2358

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, $needle)>0 ms>0 ms>0 ms>0 ms1 ms191
strpos($haystack, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms100
strstr($haystack, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms164
stristr($haystack, $needle)3 ms3 ms3 ms3 ms13 ms4733
preg_match("/$needle/", $haystack)1 ms>0 ms>0 ms>0 ms1 ms466
preg_match("/$needle/i", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms420
preg_match("/$needle/S", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms418

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 ms266
strncmp($haystack, 'needle', 6) === 0>0 ms>0 ms>0 ms>0 ms>0 ms267
strncasecmp($haystack, $needle, strlen($needle)) === 0>0 ms>0 ms>0 ms>0 ms>0 ms256
strpos($haystack, $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms499
substr($haystack, 0, strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms254
strcmp(substr($haystack, 0, strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms478
substr_compare($haystack, $needle, 0, strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms318
substr_compare($haystack, $needle, 0)>0 ms>0 ms>0 ms>0 ms>0 ms254
preg_match('/^' . preg_quote($needle, '/') . '/', $haystack)>0 ms>0 ms>0 ms>0 ms>0 ms863

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)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms228
substr($haystack, -strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms239
substr($haystack, -1) === 'n'>0 ms>0 ms>0 ms>0 ms>0 ms195
strcmp(substr($haystack, -strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms440
substr_compare($haystack, $needle, -strlen($needle), strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms285
substr_compare($haystack, $needle, -strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms261
preg_match('/' . preg_quote($needle, '/') . '$/', $haystack)>0 ms>0 ms>0 ms>0 ms2 ms2927

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, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms211
preg_replace("/$search/", $replace, $subject)>0 ms>0 ms>0 ms>0 ms1 ms248
preg_replace("/$search/S", $replace, $subject)>0 ms>0 ms>0 ms>0 ms1 ms268
strtr($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, $subject)>0 ms>0 ms>0 ms>0 ms1 ms196
strtr($subject, $fromChar, $toChar)2 ms3 ms2 ms1 ms8 ms1713
strtr($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($string, ',')>0 ms>0 ms>0 ms>0 ms>0 ms100
preg_replace('/^,*|,*$/', '', $string)>0 ms>0 ms>0 ms>0 ms1 ms1031
preg_replace('/^,*|,*$/m', '', $string)2 ms2 ms2 ms2 ms8 ms7320
preg_replace('/^,+|,+$/', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms217
preg_replace('/^,+|,+$/m', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms270
preg_replace('/^,+/', '', preg_replace('/,+$/', '', …))>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 ms195
preg_match_all('/[^,]+/', $string, $matches)>0 ms>0 ms2 ms3 ms254

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); $i++) //by reference>0 ms241
for ($i = 0; $i < count($array); $i++) //by value>0 ms209
for ($i = 0, $count = count($array); $i < $count; $i++)>0 ms100
for ($i = count($array) - 1; $i >= 0; $i--)>0 ms118
for ($i = count($array) - 1; $i >= 0; --$i)>0 ms196
$i = count($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]2 ms100
$array['key']2 ms100

My conclusion: I like associative arrays.

Implode an Array

Method Summary Index
implode(' ', $array)1 ms2519
"$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 ms3938
vsprintf('%s %s %s', $array)2 ms4318

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 ms110
"contains no dollar signs">0 ms103
'$variables $are $not $replaced'>0 ms100
"\$variables \$are \$not \$replaced">0 ms105
"$variables $are $replaced">0 ms103
$variables . ' ' . $are . ' ' . $replaced>0 ms115
$variables . " " . $are . " " . $replaced>0 ms103

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
More PHP experiments »