3v4l.org

run code in 300+ PHP versions simultaneously
<?php var_dump(json_encode(utf8_decode('föö')));
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.23, 7.4.0 - 7.4.12, 8.0.0alpha1 - rc2
bool(false)
Output for 5.2.7 - 5.2.17, 5.3.0 - 5.3.13, 5.3.15 - 5.3.29, 5.4.0 - 5.4.45
string(4) "null"
Output for 5.3.14
Warning: json_encode(): Invalid UTF-8 sequence in argument in /in/K1M3p on line 3 bool(false)
Output for 5.2.0 - 5.2.6
string(3) ""f""
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6
Fatal error: Call to undefined function json_encode() in /in/K1M3p on line 3
Process exited with code 255.
Output for 4.4.5 - 4.4.9
Fatal error: Call to undefined function: json_encode() in /in/K1M3p on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.4
Fatal error: Call to undefined function: json_encode() in /in/K1M3p on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1
Fatal error: Call to undefined function: json_encode() in /in/K1M3p on line 3