Updated: 28 September 2026 · Applies to: AlmaLinux 9, Rocky Linux 9, Ubuntu 24.04 and Debian 12
The GMP extension gives PHP fast arithmetic with very large numbers (used by some cryptography and billing code).
cPanel servers (EasyApache 4)
dnf install ea-php83-php-gmp
Or switch on php-gmp in WHM › Software › EasyApache 4 › Customize › PHP Extensions. Replace 83 with your PHP version.
Other servers
dnf install php-gmp # AlmaLinux / Rocky apt install php-gmp # Ubuntu / Debian
Then restart PHP-FPM or the web server, and check with php -m | grep gmp.
