Which Headlight Bulb Do I Need? The Ultimate Headlight Buying Guide

Up until the late-2010s, most vehicle manufacturers used either halogen or HID headlight bulbs. These bulbs burn out quickly and require frequent replacements. Luckily, there are a wide range of aftermarket LEDs available to replace these, so upgrading your vehicle lighting has never been easier! When your halogen or HID headlights burn out, use the guide below to find the right replacement bulb for your vehicle.

When replacing your vehicle lighting, you have a couple choices of light bulbs to choose from. While HID and halogen bulbs might have been more widely used in the past, LED headlights are becoming increasingly popular. Many vehicle manufacturers and those replacing burnt-out car bulbs are choosing LEDs for the following reasons:

• Long Lifespan: One of the most universal benefits of using LEDs for your headlights is longevity. LED headlights are often rated to last up to 25 times as long as their halogen counterparts, so you won’t have to worry about buying replacement bulbs in the future.

• Improved Brightness and Clarity: Even though they use less power by far, a comparable LED headlight is typically several times brighter than the halogen or HID bulb they replace. This means your vehicle can illuminate more of the road to make driving in low-lighting conditions safer and allow other drivers to see your vehicle sooner.

• More Efficient: LED bulbs use significantly less power than traditional bulbs, reducing the power demands on your vehicle's battery and alternator. 

To find the right LED replacement headlight, you must first determine the bulb type of your current headlight. The easiest way to do this is to use our Vehicle Bulb Finder. Simply plug in your vehicle’s make, model, and year and see which bulbs are compatible. This will show you the headlights that are the right size and fit for your housing. Common headlight bulb sizes include H11, 9005, H4, 9006, and H7. 

Additionally, most owner’s manuals will list the bulb type required by your car. You can also check the current headlight and check for markings indicating the part number. While this informational guide is specific to vehicle headlights, note that our Vehicle Bulb Finder also provides information for all vehicle lights, including tail, brake, turn, and fog lights.

Once you know what bulb type is compatible with your vehicle, you can start to look for the right replacement bulb. There are many different stock bulb numbers of OEM bulbs. However, a single LED type can replace multiple stock bulb numbers. For example, an H7 LED bulb can replace H7EB, H7XV, H7ST, H7CB, H7SU, and H18 OEM bulbs. Many headlight bulbs are also capable of providing fog light functionality. Our Interchange Guide provides a full list of general bulb sizes and interchange numbers.

Before choosing your replacement LED headlight, you will need to know more than just the bulb stock number. Consider the following headlight characteristics.

While LEDs generate significantly less heat than their HID and halogen bulb counterparts, they still require a method to shed excess heat for proper heat dissipation and optimal performance. Typically this is done through the use of some type of heat sink or fan system which draws heat away from the LEDs. “Fanless” headlight bulbs are typically more reliable as a result of having a simpler design, while high-powered headlights require the use of integrated fans. More recently, LED headlights have incorporated a new technology called Thermal Separation Technology (TST) that significantly increases the rate at which they are able to cool down. These technologies help make LED headlight replacements more compact, efficient, and long-lasting.

If your vehicle is CANbus equipped, then you will need CANbus-compatible bulbs. These bulbs have built-in resistors that simulate the load of the OEM halogen or HID bulb and create enough resistance on the circuit so that the CANbus system can register the replacement bulb. If you try to use a non-CANbus bulb in a system that requires one, you will most likely need a load resistor. You can also use CANbus bulbs in vehicles without a CANbus system. For more information on CANbus systems and compatible bulbs, read our FAQ here.

Our CANbus compatible bulbs will use the icon below.

There are typically two main components to a vehicle forward lighting system: headlights and fog lights. Headlight units consist of both a low beam and high beam which can either be located in separate sockets or a dual beam socket. Vehicles with separate sockets will require separate high beam and fog light replacements, whereas you can use a dual beam headlight bulb for vehicles with a single headlight unit. 

Fog lights are a separate unit typically located towards the bottom of your front bumper designed to provide extra visibility in low-visibility conditions (however, keep in mind not every vehicle has a fog light function). These lights are typically a selective yellow color which helps reduce glare from reflected light. You can choose an LED replacement bulb that offers fog light and high/low/fog functionality. Figure out which type of bulb your vehicle requires and choose a similar replacement.

Our dual-color bulbs suitable for headlight and fog light function will use the icon below.

The most common color temperature for LED vehicle headlights is a cool white light, ranging from 5000K-6500K. This color temperature is much closer to natural daylight than a halogen bulb and allows for improved visibility of road signs and obstacles. Additionally they provide a modern look that is often associated with newer cars, making them an easy upgrade to give your vehicle an high-end appearance. Certain LED headlights also come with adjustable color temperature gels that can transform the appearance of your lights. Keep in mind that some states have legislation requiring headlights to be a certain CCT, so be sure to consult your local regulations.

The most common brightness for aftermarket LEDs is between 4,000 and 6,000 lumens. However, the maximum brightness of LED headlights will depend on state regulations. Consult your local legislation and make sure there are no restrictions for aftermarket LED headlight brightness.

Many people also complain that LED headlights are “too bright” and blind oncoming traffic, but this is often the result of improperly aligned headlight bulbs. Make sure your headlights are properly positioned and aligned with our step-by-step guide here.

Polarity-sensitive bulbs have a positive and negative connection (like batteries) and will only work when the polarity is correct. If the polarity-sensitive bulb does not work when installed, turn it around in the socket. A non-polarity-sensitive bulb will work either way when installed in the socket.

Some headlight bulbs are 1:1 sized to the OEM bulb. However, more powerful replacement bulbs can be larger or differently shaped. Therefore, we recommend checking the clearance between the headlight housing and bulb assembly before deciding on a replacement option. 

Examine the physical characteristics of the bulb and housing to ensure the proper fitment before ordering where possible. Also, review the “Additional Fitment Concerns: How to Tell If The Car Bulb Will Fit” section of our Interchange Guide.

Now that you know how to select the perfect LED replacement headlight, you are ready to remove the existing light and install your new one. LED upgrades and conversion kits are made to be a simple swap, with the correct mounting flanges and connectors being pre-installed. In most cases, the hardest part of the installation is removing a bolt or two to access the bulb.

Check out our step-by-step installation video below. Most headlight bulb replacements can be done at home, but be sure to consult a certified mechanic if you run into any problems.

If you need help aligning your headlights, consult our headlight adjustment guide here.

*Headlights and headlight bulbs are under the regulation of DOT, and while an enclosed LED headlight can be street-legal, currently there are no provisions to legally allow the replacement of a halogen headlight bulb with an LED bulb. This means that all LED bulbs from all brands, regardless of claims, are not street-legal in the United States. LED headlight bulbs are, however, legal for off-road use in ATVs, UTVs, and off road vehicles, and LED fog light bulbs are street-legal in the United States.