What is the difference between GU10, E27 and MR16 lamp bases?

• Posted on 26 December 2025
• 0

GU10, E27 and MR16 refer to different types of lamp bases. They differ in connection type, voltage and application. This article helps you quickly determine which base you need for your fixture.

Anyone buying new lamps will soon encounter terms like GU10, E27 and MR16. They may sound technical, but they simply refer to the type of connection of a lamp. The base determines which lamp fits which fixture and which power supply is required. Choosing the right type prevents hassle, incorrect purchases and even compatibility issues.

E27: the classic screw base

E27 is the most well-known lamp base. The “E” stands for Edison screw and 27 refers to the diameter in millimetres. This base screws directly into the fixture. It works directly on 230V, without a transformer or driver.

Typical applications

Pendant lights
Ceiling lights
Floor lamps
Table lamps

Advantages

Easy to replace
Large range of LED, filament and design lamps

When to choose E27?
If you are looking for a general light source in living spaces and want to combine different lamp styles.

GU10: the favourite base for recessed spotlights

GU10 can be recognised by its two short pins with a wider head. You click or twist the lamp into a bayonet fitting. GU10 also works on 230V, so no transformer is required.

Typical applications

Recessed spotlights
Surface-mounted spots
Track lighting

Advantages

Compact
Directional light
Ideal for multiple light points

When to choose GU10?
If you want to install spotlights for general or accent lighting.

MR16 (GU5.3): 12V base with driver

MR16 has two thin pins and almost always operates on 12V. This means you need a transformer or LED driver between the lamp and the mains voltage. This type was widely used for halogen lighting in the past, but is now also available in LED versions.

Typical applications

Ceiling spots
Niche and accent lighting
Low-voltage situations, for example humid areas (with suitable fixtures)

Advantages

Safe low-voltage system
Often very focused light

When to choose MR16?
If you already have an existing 12V system or when an electrician specifically installs this setup.

How do you know which base you need?

Check:

The type of connection of your fixture
The voltage: 230V or 12V
The desired lighting application

Not sure? At My Planet Led, the base type and voltage are clearly listed per product, so you immediately know what you need.