My PHP Performance Benchmarks

PHP version 7.2.19 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.

Method Undefined Null False Empty string String '0' String '1' Long string Summary Index if (!$var) 4 ms >0 ms >0 ms >0 ms >0 ms >0 ms >0 ms 4 ms 451 if (empty($var)) >0 ms >0 ms >0 ms >0 ms >0 ms >0 ms >0 ms 1 ms 100 if ($var == '') 3 ms >0 ms >0 ms >0 ms >0 ms >0 ms >0 ms 4 ms 448 if ('' == $var) 2 ms >0 ms >0 ms >0 ms >0 ms >0 ms >0 ms 3 ms 333 if ($var === '') 2 ms >0 ms >0 ms >0 ms >0 ms >0 ms >0 ms 3 ms 275 if ('' === $var) 2 ms >0 ms >0 ms >0 ms >0 ms >0 ms >0 ms 3 ms 291 if (strcmp($var, '') == 0) 3 ms >0 ms >0 ms >0 ms >0 ms >0 ms >0 ms 4 ms 445 if (strcmp('', $var) == 0) 3 ms >0 ms >0 ms >0 ms >0 ms >0 ms >0 ms 4 ms 449 if (strlen($var) == 0) 3 ms >0 ms >0 ms >0 ms >0 ms >0 ms >0 ms 3 ms 353 if (!strlen($var)) 2 ms >0 ms >0 ms >0 ms >0 ms >0 ms >0 ms 3 ms 297

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.

Method Empty array 100 elements Summary Index count($array) === 0 //by reference >0 ms >0 ms >0 ms 138 count($array) === 0 //by value >0 ms >0 ms >0 ms 131 $array === [] >0 ms >0 ms >0 ms 129 empty($array) >0 ms >0 ms >0 ms 100 (bool)$array >0 ms >0 ms >0 ms 100

My conclusion: Why count if you don't care about the exact number?

Method Equal First character not equal Last character not equal Summary Index $a == $b >0 ms 1 ms 1 ms 3 ms 100 $a === $b 1 ms 1 ms 1 ms 3 ms 130 !strcmp($a, $b) 2 ms 2 ms 2 ms 6 ms 225 strcmp($a, $b) == 0 2 ms 2 ms 2 ms 6 ms 227 strcmp($a, $b) === 0 2 ms 2 ms 2 ms 6 ms 237 strcasecmp($a, $b) === 0 2 ms 2 ms 5 ms 8 ms 327

My conclusion: Use what fits your needs.

Method Not found Found at the start Found in the middle Found at the end Summary Index strstr($haystack, $needle) >0 ms >0 ms 1 ms >0 ms 2 ms 195 strpos($haystack, $needle) !== false >0 ms >0 ms >0 ms >0 ms 1 ms 100 strstr($haystack, $needle) !== false >0 ms >0 ms >0 ms >0 ms 1 ms 133 stristr($haystack, $needle) 6 ms 4 ms 4 ms 3 ms 18 ms 1877 preg_match("/$needle/", $haystack) 6 ms >0 ms 3 ms 7 ms 16 ms 1714 preg_match("/$needle/i", $haystack) 7 ms >0 ms 4 ms 7 ms 18 ms 1917 preg_match("/$needle/S", $haystack) 7 ms >0 ms 4 ms 7 ms 18 ms 1890

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.

Method Not found Found at the start Found in the middle Found at the end Summary Index $haystack[0] === 'n' >0 ms >0 ms >0 ms >0 ms >0 ms 100 strncmp($haystack, $needle, strlen($needle)) === 0 >0 ms >0 ms >0 ms >0 ms >0 ms 159 strncmp($haystack, 'needle', 6) === 0 >0 ms >0 ms >0 ms >0 ms >0 ms 120 strncasecmp($haystack, $needle, strlen($needle)) === 0 >0 ms >0 ms >0 ms >0 ms >0 ms 131 strpos($haystack, $needle) === 0 >0 ms >0 ms >0 ms >0 ms 1 ms 453 substr($haystack, 0, strlen($needle)) === $needle >0 ms >0 ms >0 ms >0 ms >0 ms 147 strcmp(substr($haystack, 0, strlen($needle)), $needle) === 0 >0 ms >0 ms >0 ms >0 ms >0 ms 206 substr_compare($haystack, $needle, 0, strlen($needle)) >0 ms >0 ms >0 ms >0 ms >0 ms 139 substr_compare($haystack, $needle, 0) >0 ms >0 ms >0 ms >0 ms >0 ms 114 preg_match('/^' . preg_quote($needle, '/') . '/', $haystack) >0 ms >0 ms >0 ms >0 ms 1 ms 533

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.

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 ms 100 substr($haystack, strlen($haystack) - strlen($needle)) === $needle >0 ms >0 ms >0 ms >0 ms >0 ms 143 substr($haystack, -strlen($needle)) === $needle >0 ms >0 ms >0 ms >0 ms >0 ms 137 substr($haystack, -1) === 'n' >0 ms >0 ms >0 ms >0 ms >0 ms 114 strcmp(substr($haystack, -strlen($needle)), $needle) === 0 >0 ms >0 ms >0 ms >0 ms >0 ms 189 substr_compare($haystack, $needle, -strlen($needle), strlen($needle)) >0 ms >0 ms >0 ms >0 ms >0 ms 141 substr_compare($haystack, $needle, -strlen($needle)) >0 ms >0 ms >0 ms >0 ms >0 ms 132 preg_match('/' . preg_quote($needle, '/') . '$/', $haystack) 1 ms 1 ms 1 ms 1 ms 3 ms 1440

My conclusion: Using substr() with a negative position is a good trick.

Method Not found Found at the start Found in the middle Found at the end Summary Index str_replace($search, $replace, $subject) >0 ms >0 ms >0 ms >0 ms >0 ms 127 preg_replace("/$search/", $replace, $subject) >0 ms >0 ms >0 ms >0 ms 2 ms 637 preg_replace("/$search/S", $replace, $subject) >0 ms >0 ms >0 ms >0 ms 2 ms 648 strtr($subject, array($search => $replace)) >0 ms >0 ms >0 ms >0 ms >0 ms 100

My conclusion: Never use the ereg…() functions.

Method Not found Found at the start Found in the middle Found at the end Summary Index str_replace($fromChar, $toChar, $subject) >0 ms 1 ms 1 ms 1 ms 2 ms 100 strtr($subject, $fromChar, $toChar) 3 ms 5 ms 6 ms 4 ms 18 ms 811 strtr($subject, array($fromChar => $toChar)) >0 ms 1 ms 1 ms 1 ms 3 ms 152

My conclusion: Since PHP 7.0 strtr() can sometimes beat str_replace() .

Method Not found Found at start Found at end Found at both sides Summary Index trim($string, ',') >0 ms >0 ms >0 ms >0 ms >0 ms 100 preg_replace('/^,*|,*$/', '', $string) 1 ms 1 ms 1 ms 1 ms 4 ms 2948 preg_replace('/^,*|,*$/m', '', $string) 6 ms 6 ms 6 ms 6 ms 24 ms 18336 preg_replace('/^,+|,+$/', '', $string) >0 ms >0 ms >0 ms >0 ms 1 ms 385 preg_replace('/^,+|,+$/m', '', $string) >0 ms >0 ms >0 ms >0 ms >0 ms 373 preg_replace('/^,+/', '', preg_replace('/,+$/', '', …)) >0 ms >0 ms >0 ms >0 ms 1 ms 603

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.

Method Empty string Single occurrence Multiple occurrences Summary Index explode(',', $string) >0 ms >0 ms 3 ms 3 ms 100 preg_split('/,/', $string) 1 ms >0 ms 4 ms 6 ms 163 preg_match_all('/[^,]+/', $string, $matches) 1 ms 1 ms 4 ms 5 ms 154

My conclusion: Don't use split() . It got deprecated in PHP 5.3 and removed from PHP 7.0.

Method Summary Index for ($i = 0; $i < count($array); $i++) //by reference >0 ms 224 for ($i = 0; $i < count($array); $i++) //by value >0 ms 236 for ($i = 0, $count = count($array); $i < $count; $i++) >0 ms 189 for ($i = count($array) - 1; $i >= 0; $i--) >0 ms 191 for ($i = count($array) - 1; $i >= 0; --$i) >0 ms 148 $i = count($array); while ($i--) >0 ms 100

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.

Method Summary Index $array[0] 10 ms 105 $array['key'] 10 ms 100

My conclusion: I like associative arrays.

Method Summary Index implode(' ', $array) 2 ms 113 "$array[0] $array[1] $array[2]" 1 ms 100 $array[0] . ' ' . $array[1] . ' ' . $array[2] 2 ms 149 sprintf('%s %s %s', $array[0], $array[1], $array[2]) 2 ms 131 vsprintf('%s %s %s', $array) 2 ms 115

My conclusion: String concatenation is a cheap operation in PHP. Don't waste your time benchmarking this.

Method Summary Index 'contains no dollar signs' >0 ms 116 "contains no dollar signs" >0 ms 106 '$variables $are $not $replaced' >0 ms 106 "\$variables \$are \$not \$replaced" >0 ms 100 "$variables $are $replaced" 3 ms 1707 $variables . ' ' . $are . ' ' . $replaced 6 ms 3836 $variables . " " . $are . " " . $replaced 6 ms 3853

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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