3v4l.org

run code in 300+ PHP versions simultaneously
<?php var_dump( preg_replace( '/foo/u', 'bar', "\xf0\x9f\xbf\xbf" ) );
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 - 5.3.23, 5.4.0 - 5.4.13, 5.4.41 - 5.4.45, 5.5.10 - 5.5.38, 5.6.0 - 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
string(4) "🿿"
Output for 5.3.24 - 5.3.29, 5.4.14 - 5.4.40, 5.5.0 - 5.5.9
NULL

preferences:
248.43 ms | 402 KiB | 399 Q