3v4l.org

run code in 300+ PHP versions simultaneously
<?php print '<script language="JavaScript">'; print 'alert("ERROR AL INTRODUCIR LOS DATOS");'; print '</script>';
Output for 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
<script language="JavaScript">alert("ERROR AL INTRODUCIR LOS DATOS");</script>

preferences:
186.29 ms | 403 KiB | 188 Q