Database diagnostic utility

Charset & Collation Checker

Inspect your MySQL or MariaDB database for charset and collation inconsistencies across tables and text-based columns.

Database analysis

Enter your database details

Connect to the database to inspect its default charset, table collations and individual text-column settings.

Read-only check

Checking database charset and collation...

IP address or hostname Database server

Port number Normally 3306

Database name Database to inspect

Database username Assigned database user

Database password Password for the database user

The initial check reads database metadata only. No tables, columns or stored data are changed while analysing the database.

Always create a complete database backup before running any generated charset or collation conversion SQL.

A character set defines which characters can be stored in the database.

A collation controls how text is compared, sorted and matched.

Tables using different collations can cause errors when queries compare or join text columns.

Modern databases will normally benefit from utf8mb4, which supports the full Unicode character range.

The exact collation you should use depends on the MySQL or MariaDB version and the application accessing the database.

Avoid converting a live production database without first testing the generated SQL on a recent backup.

Illegal mix of collations
Two compared text values use incompatible collations.

Incorrect characters
Stored text may have been imported or decoded using the wrong character set.

Truncated characters
The current character set may not support every character being saved.