When looking at the various types of bulbs, there are a few things you need to consider. When buying the right lamp for your fixture, it is important to know the different LED bulb base types to ensure you get the right one for your fixture. Here are the main LED bulb base types you need to know.


This aptly named type is shaped like the traditional light bulb most people associate with Thomas Edison. These are the most popular types of LED lights used in residential and businesses alike. When buying this type of bulb, you will see a special figure associated with each type. The E stands for Edison while the accompanying number denotes the width of the base in millimeters. Understanding these figures will help you to choose the right bulb. Here are the denotations you will most likely see:

  • E12 = Candelabra base
  • E14 = Small Edison Screw base
  • E17 = Intermediate base
  • E26 = Medium base
  • E39 = Mogul base


A bi-pin is exactly what it sounds like. It is a lamp with two pins at the base instead of a traditional screw-in style designs. Similar to the Edison denotations, a bi-pin lamp type will have a figure which helps you decipher if it is right for your fixture. They are denoted by a G followed by a number indicating the width of the space between the pins such as GU5.3 and GU10. While all pin lamps are lumped together under the bi-pin grouping for LED, there can be more than two ins to the lamp. A few common variations you might see will include options with letters such as an S for single pin, D for double pin, T for triple pin, and Q for quadruple pin.


While Edison and bi-pin are the two most common LED bulb bases, bayonet is still an option for certain bulb options. A bayonet bulb has two notes on the side which lock the bulb in place in the lamp or fixture. These come in two types: single contact denoted as SC and double contact (DC), depending on how many contact points are at the end of the bulb to connect to electricity.

You May Also Like... Other People Have Considered These Products...
View our Light Bulbs collection

Bright LED Light Bulbs for Sale

Shop our large selection of discounted light bulbs. We have the shapes, sizes and base types you are looking.

View (291) Products
View our LED Tube Lights collection.

LED Tube Light Bulbs

Shop our large selection of discounted ballast bypass and ballast compatible, T8 and T5 LED tube lights in 1, 2, 3 and 4 foot lengths.

View (90) Products
View our LED Corn Lights collection.

Corn Cob LED Bulbs

A cheap way to convert shoebox, wall pack, area, flood, cobra head lights and more to LED is to use our economical corn lights and bulbs. Just rewire the fixture, screw in and you're done quickly!

View (75) Products
You May Also Be Interested in These Articles...