3v4l.org

run code in 300+ PHP versions simultaneously
<?php $str = 'Hello World'; echo substr($str, -1); echo $str[-1];
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
dd
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33
d Notice: Uninitialized string offset: -1 in /in/FF07h on line 6
preferences:
212.76 ms | 407 KiB | 5 Q