3v4l.org

run code in 300+ PHP versions simultaneously
<?php define('FALSE', TRUE); var_dump(FALSE);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Warning: Constant FALSE already defined in /in/NBs2u on line 3 bool(false)
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.35, 5.6.0 - 5.6.40, 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
bool(false)

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213.35 ms | 403 KiB | 286 Q