In Repair & Maintenance

Most Common Light Bulb Base Types, Globe Types, and Uses

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There are a few common light bulb base types that are combined with any number of different light bulb globe shapes. The difficult part for most homeowners is that they aren’t sure which one their light fixture needs. Of course, the charts below should help you figure out to some degree what you have.

But the best way to figure out which of the light bulb base types you have is to take your bulb to the hardware store, find one that matches it, and look on the packaging to see what it’s called. Wouldn’t it be great if that was always possible? If you don’t have this perfect set up, at least check out the charts below to help you.

Common Light Bulb Base Types

common light bulb base types

Light Bulb Shape Reference

common light bulb globe types

Why are There Different Types of Bulb Bases

Life would be much simpler if you didn’t have to worry about the base type of the light bulb you needed to replace. But there are many different base types for a reason. The first reason you see different types of light bulb base types is because it restricts wattage.

You see this most commonly in twist lock light bulb base types and it is often used as a safety measure or to force energy efficiency. You will also see different light bulb base types depending on the overall size of a fixture. While bulb shape and base can be mixed and matched, you shouldn’t have a large bulb on a small base and vice-versa. The base type and the shape should be somewhat similar.

How do I Determine Light Bulb Base Type I Need

If you have the old light bulb, there is usually writing down by the base of the bulb. The writing will tell you the base type, the wattage of the bulb, the shape of the globe, and even the wavelength of light produced.

If you can’t read the writing on the bulb, or it’s gone, there is usually a sticker next to the socket that tells you similar information. You can bring in the information on the sticker to the hardware store to get the right bulb. Don’t remove the sticker, just write down the information.

Are E26 and A19 the Same

If we go back to the light bulb base types chart and the light bulb globe shapes chart, you’ll see that E26 refers to a base and A19 refers to a globe. They are a very common pairing and the vast majority of light bulbs used in modern homes are this combination.

However, the A19 globe can be combined with a GU24 base and an E26 base can be combined with a G25 globe. Of course, if you ask for either of these, the sales person at the hardware store will probably be able to figure it out with you.


Light bulbs can be confusing for most homeowners since they aren’t as simple as removing one and putting another in its place at random. There are so many light bulb base types that you need to have some idea what you need or you’ll never get it right. Fortunately, you can figure out what you have by looking at a few simple charts.