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run code in 300+ PHP versions simultaneously
<?php $str = 'ä€'; var_dump(strlen($str)); var_dump(mb_detect_encoding($str, 'auto', true)); $iso = mb_convert_encoding($str, 'iso-8859-1', 'utf-8'); var_dump(strlen($str)); var_dump(mb_detect_encoding($iso, 'utf-8, iso-8859-1', true));
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 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
int(5) string(5) "UTF-8" int(5) string(10) "ISO-8859-1"

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164.87 ms | 404 KiB | 252 Q