What is an H7 Bulb?

What is an H7 Bulb?

There are all different kinds of bulbs for your car. Knowing the difference between bulb types and determining which bulb is best for your needs can be tricky. Understanding each kind of bulb available will help you make the best choice when purchasing bulbs. In this article, we’ll focus on just one type of bulb—the H7 bulb.

Types of Bulbs

To understand exactly what an H7 bulb is, you’ll need to know a little about car bulbs in general. There are two basic categories of bulbs for vehicles. First, there are bulbs that are used for the big, important functions. These bulbs can be headlights or tail lights, but they might also be used in other parts of your vehicle.

Of course, these are going to be your brighter bulbs, as they are responsible for illuminating the road or alerting other vehicles to your presence. H7 bulbs fall into this category, and are most commonly used as headlights.

The second type of bulbs are those that may be used for signal lights or daytime running lights. In some cases, you might use an H7 bulb for these purposes, too, but this is unlikely.


So what exactly does “H7” refer to? H7 is a kind of bulb fitting. Different vehicles require different types of bulb fittings. H7 bulbs, for example, have a two-pronged plug. Other kinds of headlight bulbs have three prongs.

Because of the different number of prongs, bulb fittings are not interchangeable. If your car requires H7 bulbs, you can’t switch them out for a bulb with three prongs.


Another way in which bulbs differ from one another is in the number of filaments. Filaments are the tiny wires that, in a traditional halogen bulb, conduct electricity and get hot enough to produce light. Halogen headlight bulbs have either one or two filaments.

H7 bulbs are single-filament bulbs. Look closely at an H7 bulb, and you’ll see that there is only one wire inside.

Clearly, this makes the H4 bulb superior to most other headlight bulbs in terms of convenience. It can also save drivers time and money, as you’ll purchase fewer bulbs and save yourself the hassle of replacing both main and dipped beam bulbs.  

Halogen v LED

If you’ve done any research into the best car bulbs, or even if you’ve just purchased bulbs online before, you’ve likely seen the terms halogen, xenon, and LED. These are different types of bulbs commonly used as headlights in vehicles.

Halogen bulbs are the standard bulb found in most cars. They are the least expensive, making them easier to replace and a great choice for value. While some prefer pricier xenon bulbs, modern halogen bulbs are quite bright as well.

Xenon bulbs are a newer technology. These bulbs are filled with xenon gas, which creates a brighter light. Xenon bulbs also tend to have a cooler colour temperature, meaning they appear bluer than the yellow glow of a halogen bulb.

LED bulbs are also new to the scene. LED bulbs are longer-lasting, since they don’t rely on filaments that eventually burn out. They also produce a whiter light than halogen bulbs, which makes them a popular choice for drivers who are aiming for style.

H7 bulbs are available in both halogen and LED styles. However, LED H7 bulbs are not street legal when used as headlight bulbs. LED bulbs don’t illuminate enough of the road to operate safely as headlight bulbs.

When to Use H7 Bulbs

If you’re shopping for new headlight bulbs, you don’t have much choice when it comes to the bulb fitting. The type of bulb needed is determined by your vehicle. Many cars use H7 bulbs as headlights, most notably a variety of BMW, Audi, and Mercedes vehicles.

You can find the right bulb fitting for your vehicle using the bulb finder on our home page. If your vehicle requires H7 bulbs, check out our selection of halogen H7 bulbs, perfect for head lights. For a stylish, but likely not street-legal look, we also offer LED H7 bulbs. Learn more about the brightest H7 bulb.

Shop car headlight bulbs at PowerBulbs.