Server Requirements — CodeIgniter 3.1.5 documentation

# Server Requirements

PHP version 5.6 or newer is recommended.

It should work on 5.3.7 as well, but we strongly advise you NOT to run such old versions of PHP, because of potential security and performance issues, as well as missing features.

A database is required for most web application programming. Currently supported databases are:

> - MySQL (5.1+) via the mysql (deprecated), mysqli and pdo drivers
> - Oracle via the oci8 and pdo drivers
> - PostgreSQL via the postgre and pdo drivers
> - MS SQL via the mssql, sqlsrv (version 2005 and above only) and pdo drivers
> - SQLite via the sqlite (version 2), sqlite3 (version 3) and pdo drivers
> - CUBRID via the cubrid and pdo drivers
> - Interbase/Firebird via the ibase and pdo drivers
> - ODBC via the odbc and pdo drivers (you should know that ODBC is actually an abstraction layer)