Version 5.x System Requirements

Most current web servers with PHP & MySQL installed will be capable of running WHMCS.

Minimum Requirements

Version 6.0 is the recommended version for all new installations and upgrades.
View System Requirements for 6.0 here

• Linux or Windows OS
• PHP 5.2
  • cURL Support (with SSL)
  • GD2 Image Library
  • JSON Enabled
  • PHP Memory Limit of 64 MB
• MySQL® 4.1.x and above
  • MySQL Strict Mode disabled
• ionCube Loader® V4.0 or later

PHP 5.5 Compatibility
PHP 5.5 is not supported in WHMCS 5.3. WHMCS 6.0 supports both PHP 5.5 and 5.6.

If you would like any more information or need help in determining if your server meets these requirements, please contact us.