3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $hexed = dechex(-123); var_dump($hexed); $dehexed = hexdec($hexed); var_dump($dehexed);
Output for 4.3.0 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0
string(16) "ffffffffffffff85" float(1.844674407371E+19)