3v4l.org

run code in 300+ PHP versions simultaneously
<?php for ($a = '1a1'; $a < 2; ++$a) echo $a."\n";
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.29 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
1a1 1a2 1a3 1a4 1a5 1a6 1a7 1a8 1a9 1b0 1b1 1b2 1b3 1b4 1b5 1b6 1b7 1b8 1b9 1c0 1c1 1c2 1c3 1c4 1c5 1c6 1c7 1c8 1c9 1d0 1d1 1d2 1d3 1d4 1d5 1d6 1d7 1d8 1d9 1e0

preferences:
269.4 ms | 406 KiB | 349 Q