3v4l.org

run code in 300+ PHP versions simultaneously
<?php $book="ABC"; $name="book"; $php="name"; $language="php"; print($book); print('\n'); print($$name); print($$$php); print($$$$language);
Output for 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
ABC\nABCABCABC
preferences:
191.28 ms | 404 KiB | 256 Q