The Pros And Cons Of A H7 Headlight Bulb: Complete Guide

When looking to either purchase a new car or replace old headlight bulbs, you need to consider what bulbs are best for your specific vehicle.

Many people automatically opt for high power headlight bulbs because, well, higher power equals more power and more light, right?

The Pros And Cons Of A H7 Headlight Bulb: Complete Guide

Well, while this may be the case with some, you don’t always necessarily need a high-powered headlight bulb.

Take the H7 bulb, for example. This is a single-filament (tiny wires that conduct electricity and produce light once they are hot), low-beam headlight that lights up shorter and narrower distances.

For daytime driving, the H7 bulb is considered to be ideal. Although the H7 bulb is not high-powered, it does what it was designed for very well.

The H7 bulb has a two prong plug. This is the metallic component that fixes into a socket. Because it is two-pronged, the H7 bulb has just two wires, which are hot and neutral.

Therefore, there is no ground wire. For cars that require halogen H7 bulbs, they are not compatible with bulbs that sport three prongs. In these cars, there is little choice as to what bulbs to use.

If you want to find out more about H7 bulbs, you’re in the right place. In today’s blog, we are going to guide you through exactly what a H7 bulb is, how it works, and also look at the pros and cons of this headlight.

We will compare it with other headlights on the market so you can see where it stands in comparison.

So, before you head off and buy new H7 headlights, continue reading to see if they are the right choice for you and your vehicle.

What Is A H7 Bulb?

What Is A H7 Bulb?


A H7 bulb is a low beam headlight glass bulb. It comprises a small, thin wire filament, a glass filament, and halogen gas. Its glass filament is resistant to very high temperatures, allowing the bulb to get hot enough to shine efficiently.

This bulb sends an electric current through a wire filament within its glass filament. Here, the filaments heat up until they produce a bright yet warm yellow colored light.

The electric current works by heating the wire filament to a whopping 4,532 degrees Fahrenheit. So, don’t go touching one after it’s been on for a while!

All in all, H7 bulbs work in the same manner as traditional, standard bulbs we all use at home. However, an LED bulb is not the same.

With an LED bulb, the electricity passes through a semiconductor device known as a diode. This helps to produce a bright light. Not only this, but this process also helps to generate less heat than a H7 bulb.

While you may think that most vehicles on our roads today are fitted with LED lights, this simply isn’t the case.

Of all cars currently on the road, at least 80% are fitted with halogen headlights. Although these are the most common types of bulb, they are not as efficient as LED bulbs.

Halogen light bulbs consume quite a lot of electricity, but only have a light efficiency of approximately 2% to 4%. Therefore, they do not produce light as bright as LED bulbs.

But, before you drop your shoulders and think halogen bulbs are useless, think again! Firstly, they are not only easy to manufacture, but they are easy to install.

They are also easy to find in stores and online, so you can quickly change a faulty headlight if required. This is one of the main reasons why H7 and H7 LED bulbs are so popular among car users and car manufacturers.

H7 bulbs are compatible with most European cars, as many come with the H7 bulb as its primary option.

Examples of cars that come equipped with this stock H7 bulb are the Land Rover Discovery, Mazda 3, BMW-3 Series, Jaguar S-type, Mini Cooper, Ford Fiesta, Ford Focus, Ford Transit, Ford Galaxy, Ford Street KA, Ford Edge, Ford Cougar, and many, many more.

But, don’t think that you can go and fit any old bulb in your car without checking. The UN (United Nations) has international guidelines set out to classify what bulbs can be used for headlights.

These are categorized into three groups – group 1, group 2, and group 3. For headlights, these fall into group one alongside tail lights, and fog lights.

The Pros And Cons Of H7 Bulbs


While there are some disadvantages to using H7 headlight bulbs, there are many advantages to using them, too. Some pros of using H7 bulbs include:

  • Inexpensive
  • Good for daily driving
  • Do not blind oncoming motorists
  • Easy to install
  • Can be dimmed if necessary
  • Can improve low visibility driving scenarios
  • Emit a warm color
  • Offer versatility

As we have already touched upon, H7 bulbs are cheap to manufacture, easy to replace and install, emit very bright yellow-white lights, and, perhaps most pleasingly, they tend to last up to 1,000 hours in normal conditions, on average.

Very importantly, when used on the road, they light up the road very well without blinding any oncoming motorists.

Today, however, many new vehicles are being made with LED and xenon bulbs. You may think that using a H7 LED headlight bulb can be used but, unfortunately, these remain illegal for vehicles to use on streets.

When you consider that the Insurance Institute for Highway Safety (IIHS) has stated that LEDs are the superior performers when tested against other types of bulbs, the fact you can’t use H7 LED headlight bulbs seems somewhat bizarre.

But, overall, some halogen bulbs work much better than many LED bulbs.

It goes without saying, but your illumination from your headlight bulbs is critical for safer roads and driving.

IIHS experts found that a driver typically takes 1.5 seconds to react to an unforeseen occurrence. When a vehicle is traveling at 55 mph, it will cover approximately 120 feet during 1.5 seconds.

This is even when the brakes are applied fully. But, on average, it will take over 144 feet to stop the car at such a speed.

If headlight beams are not strong enough to see something up ahead, the driver may not have enough time to react to avoid a catastrophic situation.

The IIHS experts concluded that the majority of low beam headlights, that have poor ratings, do not generate enough illumination for motorists traveling at 55 mph.

Therefore, these lights are not adequate to allow a driver the time to stop after seeing an obstacle in the road ahead.

Moreover, headlight beams with low ratings also provide less light when traveling around curves, so situations may not be picked up soon enough.

Let’s take a look at some main advantages of using H7 headlight bulbs.


Because H7 bulbs only have one filament, they are much more affordable compared to other headlight bulb types. Not only are they cheaper to buy, but they are cheaper to mass produce and repair.

While the price of a pair of H7 headlight bulbs is generally around the $30 mark, they should last for fifteen months or more. That results in good value for money!

Good For Daily Driving

H7 headlight bulbs have an output of 1350 lumens at 6V-12v. This is at their maximum and stick within U.S. guidelines. They also have a low beam pattern, making them suitable for daytime driving.

When we consider that all cars have a maximum wattage upper limit and the H7 bulb has a maximum power of 55W and a nominal power of 45W, it means these bulbs can be used for daily driving without any issues.

Do Not Blind Oncoming Motorists

Ever been driving along a straight road only to be blinded by what looks like starlight coming towards you? If so, those bulbs were probably High-Intensity Discharge (HID).

These generate very bright lights and shine into the eyes of oncoming drivers.

H7 bulbs, however, emit a warmer, yellow light. The filament of these bulbs is kept in a housing that helps prevent the bulbs from blinding other motorists.

H7 lights cover short and narrow distances, allowing pedestrians, cyclists, and drivers full visibility of their road ahead. Therefore, the overall road environment becomes safer with a lower risk of accidents.

Easy To Install

When it comes to replacing and installing new H7 headlight bulbs, it’s a straightforward process. As with any vehicle, you should follow the owner’s manual when installing new headlight lamps.

You can also follow the instructions that come with H7 bulbs.

The same can’t be said about HID H7 bulbs, however. While H7 headlight bulbs click into places easily, HID H7 bulbs are more difficult to install as they require a ballast.

This is a device that gives you the voltage a lamp requires to light up. It then regulates the voltage and electric current during the process.

Can Be Dimmed

Can Be Dimmed

Although HID H7 headlight bulbs require a few seconds to reach their maximum brightness and warm up, regular H7 headlight bulbs need less energy to light up.

When you turn them on, they immediately provide you with their full illumination.

Not only this, but H7 bulbs are also dimmable. This allows you to set them to different levels of brightness, such as low beam or high beam.

Can Improve Low Visibility Driving Scenarios

The H7 headlight bulb is low-beam. Therefore, it is permitted by U.S. law to be used for regular nighttime driving.

Moreover, H7 headlight bulbs complement low visibility driving conditions such as snow, fog, rain, and dust.

If your vehicle’s fog lights don’t work properly, H7 bulbs can become a good alternative as their warm, yellow glow can cut through fog and rain well.

Emit A Warm Color

H7 headlight bulbs emit a warm yellow, almost white color of 2300K to 5000K (Kelvin).

In comparison to HID headlights that generated a light-blue hue of 4000K to 6000K, the warmer color of H7 bulbs are more road friendly and easier on the eyes.

Offer Versatility

Because H7 bulbs are available in various sizes, they can fit most car models. Whether the vehicle is new or old, H7 headlight bulbs tend to be compatible. Vehicles they fit include sedans, SUVs, and motorcycles.

Now we have studied the overall benefits and pros of using H7 headlight bulbs, it’s only fair that we turn the tables and take a look at the disadvantages of using them.

Therefore, you can have a clearer picture of whether you want to use them in your vehicle, or not.


In the current automotive manufacturing industry, many companies are using H7 halogen headlight bulbs as their second choice. Instead, H7 LED bulbs are the preferred choice by many today.

You may be wondering why after seeing all of their benefits above, but there are some reasons including their lower efficiency compared to others, their fragility, and the fact that they are prone to wasting energy.

As time ticks on, halogen headlights tend to become duller. Therefore, the light they emit becomes weaker, resulting in a less safe and older looking car.

Remember, the headlights of a car are critical to safety on our roads. If you can’t rely on them to cast a wide light onto the road ahead of you, then you are putting yourself and others using the road at risk.

The main drawbacks of using H7 headlight bulbs are:

  • Not energy efficient
  • Have a short life span
  • Only illuminate a short distance ahead
  • Poor brightness level
  • Less elegant than others
  • Prone to overheating

Not Energy Efficient

There’s no getting away from it – H7 headlight bulbs are not energy efficient.

Yes, they produce light via their heating filaments, and these generate a great deal of heat but, this equates to wasted energy and it can actually reduce your car’s battery life.

HID bulbs, on the other hand, are capable of cutting energy used by up to 25 to 30%.

Overall, H7 headlight bulbs use a lot of energy to produce any kind of light, but LED bulbs use only a fraction of energy to generate the same amount of illumination.

Short Life Span

Under standard conditions, a H7 bulb will last around 10,000 hours, on average. Compared to other types of bulbs, this life span is relatively short. This is mainly down to the fact that H7 bulbs tend to react to certain substances.

For instance, when you need to change the bulb, you could reduce its life span by simply touching the glass with greasy hands.

Just a small amount of grease can impact the heat as this will become uneven and could damage the glass casing. Moreover, H7 bulbs are made with high-pressure halogen, resulting in an increased fragility.

Only Illuminate A Short Distance Ahead

H7 headlight bulbs are not known for their long distance illumination. On average, they can typically only light up around 150 to 200 feet in front of your vehicle.

Although its lower brightness level is an advantage, as it doesn’t blind oncoming drivers, it is also a disadvantage. This is because it provides poorer visibility on the road during nighttime.

If an obstacle suddenly appears on the road ahead of you and your lights are not bright enough to see it soon enough, there is a higher chance of an accident occurring.

In general, H7 headlight bulbs only light up around your vehicle and not the whole road ahead.

Poor Brightness Level

Moving on from our last point, H7 bulbs generate a lower level of brightness compared to HID headlights. While a HID bulb provides 3000 lumens, a standard H7 headlight bulb only gives 1350 lumens.

Therefore, the road ahead of you may not be lit up enough to see everything with H7 bulbs.

Less Elegant Than Other Bulbs

Over time, H7 headlight bulbs tend to become duller. Not only does this mean they are less powerful, but they can make your car look older and duller, too.

HID bulbs offer a more contemporary, clean, and stylish look for cars, whereas H7 bulbs are not as elegant.

Prone To Overheating

As we have mentioned, H7 bulbs need to heat up considerably to shine efficiently. However, there have been many issues surrounding overheating H7 bulbs.

This generally occurs when the wire in the filament burns out and gets left on the bulb’s glass. This leads to the bulbs becoming unusable.

If you handle a H7 bulb after it’s been used, it can cause burns to your skin. LED bulbs, however, emit a very small amount of heat, meaning they are typically safer to use.

Maintaining H7 Headlight Bulbs

If your car has H7 headlight bulbs installed, it is important that you maintain them properly for long-lasting use. Below are some common issues with H7 lights and ways of looking to fix such problems.


As you drive, you will come across vibrations on the road. Unfortunately, H7 bulbs are somewhat sensitive to vibrations and, when exposed to excessive vibration, they can become damaged or even explode.

When you install a H7 bulb, ensure that it is secured tightly. Check that all bolts are tight with no cracks on any headlight bolt, too.

If you inspect the connectors and find that they have burned, melted, or show signs of corrosion, replace them immediately.

Regular maintenance of a vehicle is critical to keeping on top of things and ensuring that it lasts as long as possible.

When you are checking your H7 headlight bulbs, you should also inspect your car’s suspension, suspension springs, and wheel bearings. In other words, check any component that may cause a vehicle to vibrate.

Loose Wiring

Sometimes, loose wiring can occur around your H7 headlight bulbs. If this happens, an electric current may get into contact intermittently.

Over time, this can lead to a buildup of heat and the possibility of overheating.

If the temperature goes beyond what a H7 bulb can resist, then its filament will most likely blow. We recommend using an automotive circuit tester to check for loose wiring.


If your headlight has a build up of condensation, then it could result in an electric short circuit. The result? A damaged bulb.

This is why you should regularly inspect your headlights to ensure there is no excessive moisture inside them.

Most headlights require a continuous airflow, so heat is controlled efficiently and moisture is prevented or reduced from building up in the lens.

This airflow is possible thanks to ventilation through the top and base of the headlight in the form of tubes or small holes.

When checking your headlights, inspect the bulb’s back cover mounting. Ensure this is in place properly and if the seal surrounding the lens is damaged or not. If so, it may need replacing.

Repairing Broken H7 Headlight Bulbs

If your H7 headlight bulbs are not working correctly, you will need to inspect them for any damage. They may need repairing or replacing completely.

Here’s how to check your H7 headlight bulbs and repair them if necessary:

  1. Start by parking your car and turning the engine off.
  2. Open your car’s hood and check around the base of the headlight. Here, you will find the bulb holder.
  3. Once you have located the bulb holder, you should find that it has three wires that connect to the plug. However, a few cars have a screw cap, whereas others come with a clip that holds the plug firmly in position. Here, pull the cap off by turning it clockwise.
  4. As you’re holding the plug, take the bulb out of its socket. Make sure you do not squeeze the bulb too much as this may break the bulb, and, even worse, it could cause an injury to yourself.
  5. Check the bottom of the old, faulty bulb and compare it with your new H7 bulb. Make sure they have the same shape, fitting, and base. If all goes smoothly, the new bulb will have the same base as the old one. If this is the case, you can simply insert the new bulb into the same position as the old one was in. It’s important to note, however, that H7 bulbs are extremely sensitive to oils and grease. Therefore, you must ensure that your hands are completely clean and oil-free before handling the bulb. And, when you hold it, don’t touch the glass – only hold a H7 bulb by its metal base.
  6. Once you have placed the new bulb into position carefully and securely, you need to reconnect the wiring. Remember to return the cap or clip that was holding the headlight assembly in place back into its original location.
  7. Once everything has been connected and the bulb is firmly in place, you need to check that your new H7 bulb is working. Do this before you close your hood. Simply switch on your vehicle and turn your headlights on. Go round the front of your vehicle, or have another individual do so, to see if the bulbs lights up. Then, make sure the bulb’s alignment is even.
  8. Once this has all been checked and everything is in working order, you can close your hood and enjoy your new H7 headlight bulbs.

The Best H7 Bulbs

If you believe that H7 headlight bulbs are the right choice for your vehicle, you will want to find the brightest, best ones on the market.

But, with so many available, it can be a little mind-boggling shifting through each one to find the best H7 bulb for you.

Not to worry, though, as we have a selection of top-quality H7 bulbs to take a look at below.

HELLA H7 Standard Halogen Bulb

HELLA H7 Standard Halogen Bulb, 12 V, 55W

These H7 bulbs from HELLA offer a superb lighting performance for increased visibility and comfort on the road.

Coming from a renowned manufacturer, such as HELLA, you can be sure that you’re getting top-quality bulbs that you can trust.

ELLA are known for their great functionality, long-lasting use, and compatibility with most vehicles.

But, if you decide to change a H7 bulb, we recommend changing them in pairs to achieve a symmetrical light beam from the two bulbs.

Therefore, there is less chance of blinding other drivers on the road and seeing one of your headlights get dimmer over time.

HELLA H7 Standard Halogen Bulb, 12 V, 55W
5,899 Reviews
HELLA H7 Standard Halogen Bulb, 12 V, 55W
  • Get the best lighting performance and an increased visibility and...
  • Original equipment quality bulbs you can trust from a global leader in...
  • HELLA bulbs guarantee best functionality, optimum fit and long lasting...

Philips X-tremeVision Pro150 Xtreme Vision Pro 150 Car Headlight Bulbs H7

Philips X-tremeVision Pro150 Xtreme Vision Pro 150 Car Headlight...

The Philips X-tremeVision Pro150 headlight bulbs are another example of high-quality from a respected brand.

These H7 headlight bulbs are up to 150% brighter than your standard halogen bulbs, making them the preferred choice by many on the road.

The brightness from these Philips H7 bulbs can illuminate up to around 70 meters of the road ahead of you and, because H7 bulbs are known for their sensitivity, these come with an advanced filament design and Diamond Precision Quartz.

Together, this technology strengthens these bulbs with additional protection.

Philips X-tremeVision Pro150 Xtreme Vision Pro 150 Car Headlight...
85 Reviews
Philips X-tremeVision Pro150 Xtreme Vision Pro 150 Car Headlight...
  • Up to 150% brighter than standard halogen
  • Illuminate up to 70 metres more of the road ahead
  • Advanced filament design and 'Diamond Precision' Quartz glass...

PHILIPS – Diamond Vision H7 Halogen HID Bulbs

PHILIPS - Diamond Vision H7 Halogen HID Bulbs (Pair)

We thought we’d stick with Philips as the brand is renowned for world-class H7 bulbs around the world.

But, these are strictly for off-road use only, as Philips Diamond Vision H7 bulbs are not road legal in the U.S. at the moment.

Imported from Europe, these Diamond Vision H7 Halogen HID bulbs not only emit a bright 5000k white light but they also look fantastic on cars with their diamond vision.

Although standard H7 bulbs have a yellow tint to them, these are white, offering greater visibility and light output.

PHILIPS - Diamond Vision H7 Halogen HID Bulbs (Pair)
3,765 Reviews
PHILIPS - Diamond Vision H7 Halogen HID Bulbs (Pair)
  • Original Philips Item, imported from Europe. Diamond Vision series do...
  • Philips Diamond Vision Halogen headlight is the ultimate style upgrade...
  • The color temperature of these bulbs is 5000K. The standard unit for...

The Differences Between H7 And H4 Bulbs

A common query many have is, ‘what are the differences between H4 and H7 headlight bulbs?’ Well, the H7 bulb has a single filament. Therefore, it utilizes two bulbs (main beam bulb, and a dipped beam bulb).

The H4 bulb, on the other hand, is a two filament bulb. Therefore, it can function as a main beam and dipped beam bulb simultaneously.

Moreover, H7 bulbs have a two-pronged base, whereas an H4 version has a three-pronged base.

How To Find Out What Type Of Bulb Your Vehicle Has?

To find out what type of bulb your car uses, you need to discover what type of fitting or cape it has, as well as what adaptor it requires.

You can typically find a car’s bulb labeled with numbers and/or letters. The numbers represent the base’s diameter in millimeters, whereas the letters represent the type of base it has.

You may also find another number to display the number of pins the plug has.

Most commonly, car bulb bases and caps are pins and screws. Screws tend to be labeled with the letter ‘E.’

How To Find Out What Size Bulb Your Car Has?

To find out the size of your vehicle’s bulb, you need to check its diameter and the widest point in the sizes of bulbs. Then, measure the bulb in ⅛ of an inch.

Some examples include an A21 bulb which is 21 eighths, while a T12 bulb is 12 eights. By checking these, you can find out the size of your car’s bulb.

In Summary

There are many pros and cons surrounding H7 headlight bulbs. Yes, they are affordable, simple to install, and fit most cars.

But, they are sensitive and tend to have quite a short life span. They are also not energy efficient and do not have a long range of illumination.

While H7 halogen headlight bulbs do what they are designed to do, other types of high-quality bulbs are typically the preferred option these days.