The mini-DIN connectors are a family of multi-pin electrical connectors used in a variety of applications. Mini-DIN is similar to the larger, older DIN connector. Both are standards of the Deutsches Institut für Normung, the German standards body.

Standard connectorsMini-DIN connectors are 9.5 mm in diameter and come in seven patterns, with the number of pins from three to nine. Each pattern is keyed in such a way that a plug with one pattern cannot be mated with any socket of another pattern. An important aspect of why each of these 7 mini-DIN connectors are official standards is because they are each drastically different from the other, with no simultaneously and directly overlapping similarities in (1) pin arrangement, (2) square key size and position, (3) circular shielding metal skirt notches & metallic additions - unlike the nonstandard mini-DIN connectors which may have directly overlapping characteristics to each other or to the standard mini-DIN connectors.

The 3-pin Mini-DIN connector must not be mixed up with a similar looking, but more rugged 3-pin DC power connector sometimes erroneously also referred to as "Mini-DIN" connector.

The 4-pin Mini-DIN connector must not be mixed up with a similar looking, but more rugged 4-pin DC power connector sometimes erroneously also referred to as "Mini-DIN" connector.

The 5-pin MIDI input and output connectors used by the Creative Technology Sound Blaster X-Fi and Audology 2 ZS front I/O panel, and the Creative LivedriveII (pinout diagram).

Being an internal bus, there is no standard connector for I²C, but the 6-pin mini DIN is often used for I²C where external connections are required, such as in measurement and control equipment with a documented pinout.

The mini-DIN 9-pin diagram is not the standard mini-DIN; the standard has nonuniform spacing on the first row and uniform spacing on the second. A data sheet for mini-DIN 9 connector shows this pattern.