3v4l.org

run code in 300+ PHP versions simultaneously
<?php $n =0; for($i=0;$i<10;$i++){ echo $i.$i; }
Output for 7.3.0 - 7.3.29, 7.4.0 - 7.4.21, 8.0.0 - 8.0.8
00112233445566778899

preferences:
199.52 ms | 459 KiB | 5 Q