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 (!$var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms388
if (empty($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 ms485
if ('' == $var)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms499
if ($var === '')>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms509
if ('' === $var)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms619
if (strcmp($var, '') == 0)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms1158
if (strcmp('', $var) == 0)1 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms1179
if (strlen($var) == 0)>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms1 ms474
if (!strlen($var))2 ms>0 ms>0 ms>0 ms>0 ms>0 ms>0 ms2 ms1731

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($array) === 0 //by reference>0 ms>0 ms>0 ms224
count($array) === 0 //by value>0 ms>0 ms>0 ms160
$array === []>0 ms>0 ms>0 ms100
empty($array)>0 ms>0 ms>0 ms100
(bool)$array>0 ms>0 ms>0 ms244

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 ms199
$a === $b>0 ms>0 ms>0 ms>0 ms100
!strcmp($a, $b)1 ms1 ms1 ms2 ms1083
strcmp($a, $b) == 01 ms1 ms1 ms2 ms1049
strcmp($a, $b) === 04 ms1 ms1 ms6 ms3141
strcasecmp($a, $b) === 01 ms1 ms2 ms3 ms1610

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, $needle) !== false>0 ms>0 ms>0 ms>0 ms>0 ms155
stristr($haystack, $needle)3 ms3 ms3 ms3 ms11 ms4858
preg_match("/$needle/", $haystack)7 ms>0 ms>0 ms>0 ms8 ms3218
preg_match("/$needle/i", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms482
preg_match("/$needle/S", $haystack)>0 ms>0 ms>0 ms>0 ms1 ms426

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
$haystack[0] === 'n'>0 ms>0 ms>0 ms>0 ms>0 ms146
strncmp($haystack, $needle, strlen($needle)) === 0>0 ms>0 ms>0 ms>0 ms>0 ms147
strncmp($haystack, 'needle', 6) === 0>0 ms>0 ms>0 ms>0 ms>0 ms109
strncasecmp($haystack, $needle, strlen($needle)) === 0>0 ms>0 ms>0 ms>0 ms>0 ms114
strpos($haystack, $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms257
substr($haystack, 0, strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms123
strcmp(substr($haystack, 0, strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms224
substr_compare($haystack, $needle, 0, strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms153
substr_compare($haystack, $needle, 0)>0 ms>0 ms>0 ms>0 ms>0 ms100
preg_match('/^' . preg_quote($needle, '/') . '/', $haystack)>0 ms>0 ms>0 ms>0 ms>0 ms340

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)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms225
substr($haystack, -strlen($needle)) === $needle>0 ms>0 ms>0 ms>0 ms>0 ms213
substr($haystack, -1) === 'n'>0 ms>0 ms>0 ms>0 ms>0 ms194
strcmp(substr($haystack, -strlen($needle)), $needle) === 0>0 ms>0 ms>0 ms>0 ms>0 ms364
substr_compare($haystack, $needle, -strlen($needle), strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms237
substr_compare($haystack, $needle, -strlen($needle))>0 ms>0 ms>0 ms>0 ms>0 ms298
preg_match('/' . preg_quote($needle, '/') . '$/', $haystack)>0 ms>0 ms>0 ms>0 ms2 ms2804

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, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms169
preg_replace("/$search/", $replace, $subject)>0 ms>0 ms>0 ms>0 ms1 ms358
preg_replace("/$search/S", $replace, $subject)>0 ms>0 ms>0 ms>0 ms>0 ms254
strtr($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, $subject)>0 ms>0 ms>0 ms>0 ms1 ms122
strtr($subject, $fromChar, $toChar)2 ms3 ms3 ms3 ms11 ms1505
strtr($subject, array($fromChar => $toChar))>0 ms>0 ms>0 ms>0 ms1 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($string, ',')>0 ms>0 ms>0 ms>0 ms>0 ms100
preg_replace('/^,*|,*$/', '', $string)>0 ms>0 ms>0 ms>0 ms1 ms1108
preg_replace('/^,*|,*$/m', '', $string)2 ms2 ms2 ms2 ms7 ms5757
preg_replace('/^,+|,+$/', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms193
preg_replace('/^,+|,+$/m', '', $string)>0 ms>0 ms>0 ms>0 ms>0 ms149
preg_replace('/^,+/', '', preg_replace('/,+$/', '', …))>0 ms>0 ms>0 ms>0 ms>0 ms295

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 ms9 ms9 ms923
preg_match_all('/[^,]+/', $string, $matches)>0 ms1 ms2 ms3 ms304

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); $i++) //by reference>0 ms274
for ($i = 0; $i < count($array); $i++) //by value>0 ms256
for ($i = 0, $count = count($array); $i < $count; $i++)>0 ms100
for ($i = count($array) - 1; $i >= 0; $i--)>0 ms117
for ($i = count($array) - 1; $i >= 0; --$i)>0 ms130
$i = count($array); while ($i--)>0 ms170

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]4 ms100
$array['key']19 ms440

My conclusion: I like associative arrays.

Implode an Array

Method Summary Index
implode(' ', $array)1 ms1953
"$array[0] $array[1] $array[2]">0 ms100
$array[0] . ' ' . $array[1] . ' ' . $array[2]>0 ms100
sprintf('%s %s %s', $array[0], $array[1], $array[2])2 ms3032
vsprintf('%s %s %s', $array)2 ms3120

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 ms104
"contains no dollar signs">0 ms104
'$variables $are $not $replaced'>0 ms105
"\$variables \$are \$not \$replaced">0 ms100
"$variables $are $replaced">0 ms111
$variables . ' ' . $are . ' ' . $replaced>0 ms100
$variables . " " . $are . " " . $replaced>0 ms149

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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