3v4l.org

run code in 300+ PHP versions simultaneously
<?php $v1 = 5; $v2 = '5-4'; $time = microtime(1); $i = 0; while($i++ < 1000000) echo ' ',' ',' ',' ',' '; echo (microtime(1)-$time)." seconds for commas"; echo "\n"; $time = microtime(1); $i = 0; while($i++ < 1000000) echo ' '.' '.' '.' '.' '; echo (microtime(1)-$time)." seconds for dot";
Output for 5.4.39 - 5.4.45, 5.5.22 - 5.5.38, 5.6.6 - 5.6.38, 7.0.0 - 7.0.31, 7.1.0 - 7.1.22, 7.2.0 - 7.2.10

Process exited with code 137.
preferences:
245.84 ms | 438 KiB | 128 Q