# MD5

## Syntax

```sql
MD5(str)
```

## Description

Calculates an MD5 128-bit checksum for the string.

The return value is a 32-hex digit string, and a nonbinary string in the connection [character set and collation](https://mariadb.com/docs/server/reference/data-types/string-data-types/character-sets), determined by the values of the [character\_set\_connection](https://mariadb.com/docs/server/server-management/variables-and-modes/server-system-variables#character_set_connection) and [collation\_connection](https://mariadb.com/docs/server/server-management/variables-and-modes/server-system-variables#collation_connection) system variables.

`NULL` is returned if the argument was `NULL`.

{% hint style="warning" %}
**Don't use this function as an encryption function.**

MD5 can be used as a checksum to verify data integrity against unintentional corruption. Historically it was widely used as a cryptographic hash function; however it has been found to suffer from extensive vulnerabilities.

See <https://en.wikipedia.org/wiki/MD5> for details.
{% endhint %}

## Examples

```sql
SELECT MD5('testing');
+----------------------------------+
| MD5('testing')                   |
+----------------------------------+
| ae2b1fca515949e5d54fb22b8ed95575 |
+----------------------------------+
```

<sub>*This page is licensed: GPLv2, originally from*</sub> [<sub>*fill\_help\_tables.sql*</sub>](https://github.com/MariaDB/server/blob/main/scripts/fill_help_tables.sql)

{% @marketo/form formId="4316" %}


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