3v4l.org

run code in 300+ PHP versions simultaneously
<?php $f = 2.344567789877; printf('%e', $f);
based on bev1o
Output for 7.3.0 - 7.3.28, 7.4.0 - 7.4.16, 8.0.0 - 8.0.3
2.344568e+0