9003 vs H4 – Similarities and Differences Between 9003 and H4 Headlight Bulbs

9003 vs H4: Although similar in very many aspects, the 9003 headlight bulbs are not the same as H4 headlight bulbs.

H4 bulbs are mainly used for motorcycles and off-road vehicles since they are not legal to be used by cars on public roads.

The 9003 dual-beam headlight bulbs are, on the other hand, legal, since they are safe for other drivers as well.

In the lines that follow, you will find out more about the differences and similarities between 9003 and H4 bulbs.

What is 9003 Headlight Bulb?

If you’re looking to use one single bulb for both the high and low beams, a 9003 headlight bulb will do the job.

Featuring two filaments, it can serve both purposes, without the need to buy two bulbs, one for each beam.

It is possible to use a 9003 headlight bulb as a fog light as well and many car owners do so. Even motorcycles use this type of headlight bulb.

To tell whether your car is compatible with a 9003 headlight bulb, you need to remove the old bulb and see the headlight’s socket.

Sockets suitable for 9003 bulbs will feature three wires. More precisely, there will be a black (ground) wire, a red wire (high beam), and a yellow wire (low beam).

Also, 9003 bulbs are easy to recognize. It is possible to spot the double filament and three prongs that can be seen at the base.

What is H4 Headlight Bulb?

An H4 headlight bulb also features two filaments, allowing users to connect it to both the low and high beams.

When it first appeared, this headlight bulb was destined to be used by race cars. For improving the visibility of drivers they provide very bright light.

In the US, these bulbs were illegal for cars, so they found users among motorcycle owners.

These days, H4 headlight bulbs are legal, as long as they are equipped with LED technology.

This way, there is no risk for the bright light to blind other drivers on the road.

What Car Does a 9003 Bulb Fit on?

To check whether a car is compatible with a 9003 bulb, you will need to see the back of the headlight.

For this, the old or stock bulb must be removed. If the back of the headlight features three tabs, then it is possible to mount a 9003 bulb on.

More precisely, if the car features a DOT HB2 assembly, there shouldn’t be any issues with using a 9003 bulb.

In case the bulb won’t fit properly in the socket, it is possible to use an adapter to make it fit. Just remember you’ll have to buy the adapter separately.

9003 vs H4: How Are They Different?

01. Brightness

In terms of brightness, the bulbs provide similar light.

They are also available in a variety of lumen options, so you can choose based on your needs.

However, do bear in mind that LED bulbs provide a brighter and whiter light than halogen bulbs.

02. Spread

The spread of the bulbs depends on their brightness. The brighter the output light is (the more lumens it has), the further the beam will go.

Modern LED headlight bulbs these days are made to be bright and effective, while not blinding drivers coming from the opposite lane.

03. Energy Consumption

The wattage of 9003 bulbs ranges between 55 and 60, while H4 bulbs usually feature a wattage of 55. So, their energy consumption is similar.

04. Efficiency

If the bulbs were rather similar up to this point when it comes to efficiency things change a little.

H4 bulbs are not built that well, which can make the beam quite uncomfortable for other drivers (the beam is not directed as it should on the road).

The 9003 bulbs appeared as a response to H4 bulbs so that drivers can enjoy the same effect, but better in terms of quality.

So, the 9003 bulbs are more effective if we are to look at the projected beam and light quality.

05. Structure

Although the bulbs look the same, on the outside, a closer look will reveal several differences.

Even though three prongs are emerging on the base of both bulb models, there are differences in their size.

The 9003 bulbs will have all three prongs of equal sizes, while the H4 bulbs feature one shorter tab at the bottom.

This will create fitting problems, as an H4 bulb will fit both an H4 and 9003 housing, but a 9003 bulb won’t fit H4 housing.

06. Durability

If you want durable headlight bulbs that don’t need replacement anytime soon, always go for LED bulbs.

LED headlight bulbs can last approximately 30,000 hours, while halogen bulbs have a much shorter lifespan, of only a couple of hundred hours of light.

07. Legality

The Department of Transportation didn’t approve H4 beams for cars, so they mostly found users among motorcycle drivers.

This was due to the intensity of the beam and various pattern output, which could become bothersome or blinding for other drivers.

Thus, the 9003 bulbs were developed instead (in Europe, it is called HB2).

The 9003 bulbs can be used without issues by drivers in the US since the pattern is improved and there’s no risk of blinding others.

08. Safety

As mentioned earlier, the 9003 bulbs are safer to be used than H4 bulbs, because the pattern is stable, the brightness is good without being a nuisance and they are easier to mount in the housing of the headlight.

09. Price

Regarding prices, H4 bulbs are a bit more expensive than 9003 bulbs.

At the same time, in the US, 9003 bulbs are more suitable to be used as headlights for vehicles, while H4 bulbs are used for motorcycles.

10. Pros

9003 bulbs are more suitable for cars than H4 bulbs, although it is possible to use H4 bulbs if you go for LED versions, which are better in terms of quality;

11. Cons

You need to check whether your car is compatible with double-filament bulbs, featuring three wires at the back of the headlight;

H4 Bulb vs 9003: Which Bulb is Better?

In case your car is compatible with a double-filament bulb, the 9003 is a much better option.

Not only is it legal, but it is also easier to mount in the housing without risking affecting the quality of the beam.

While it is true that H4 bulbs are brighter than 9003, it is precisely why they were considered inadequate by the Department of Transportation.

They can blind oncoming drivers, so it is safer to choose 9003 bulbs for your car. 9003 bulbs are also more economical in terms of energy consumption.

Because they usually feature fewer lumens, they will not need that much energy to function. However, the difference is not that noticeable.

If you’re interested in H4 bulbs, do know that they are accepted only on motorcycles and off-road vehicles.

If you intend to drive your car on public roads, you’ll need to equip it with 9003 bulbs to respect the law, since H4 bulbs are considered a safety hazard for other drivers.

All in all, 9003 bulbs are better for cars that roll on public roads simply because it is a legal option. If you mount H4 bulbs on your car, you might get in trouble with the police.

9003 vs 9004: Are They Similar?

9003 bulbs are not similar to 9004 bulbs, the main difference being in their case.

These two types of bulbs are not interchangeable since a 9004 bulb will not fit in the housing of a 9003 bulb and the other way around.

Only 9007 bulbs could replace 9004 bulbs, but only in some cases and if certain modifications are done.

There is also a difference when it comes to light patterns. The 9004 bulb has a transverse filament, while the 9003 bulb has a longitudinal filament.

The position of the filament will have, obviously, implications on the way light is emitted and how the beam is formed.

In conclusion, your car cannot work with both of these bulbs. You need to check compatibility before buying a headlight bulb.

The base of the bulb must fit well in the housing to get the best the bulb has to offer.

Of course, there are cases in which an adapter can solve fitting problems, so check if this is possible in your case.

Are 9003 and H4 Interchangeable?

The 9003 and H4 bulbs are almost the same kinds of bulbs since the 9003 bulbs appeared out of the desire to put on the market a more improved (and legal) version of the H4 bulb.

So yes, if you want an H4 bulb that is legal, your choice should be the 9003 bulbs. However, bear in mind what we talked about earlier.

An H4 bulb can fit in a 9003 socket, but a 9003 bulb cannot fit in an H4 socket, because the H4 has one of the three prongs shorter.

But, in general, car owners should not come across difficulties in using 9003 bulbs, as long as their headlights accommodate three wires that make the bulb fit.

Due to the three prongs and dual-filament design, one 9003 bulb can be used for the high and low beams alike.

H4 vs 9003: How To Know Which One Do You Need?

If you need a headlight bulb to illuminate the road while driving on public roads, then you should choose a 9003 bulb.

H4 bulbs are illegal to be used on public roads. You can use H4 bulbs only for a motorcycle or vehicle you intend to drive off public roads.

Thus, this is how you know how to make the best decision.

H4 bulbs initially developed in Europe for sportscars, are illegal in the US since the bright beam can blind other drivers.

The better and safest option for cars is the 9003 bulb.

How to tell whether you need a 9003 bulb or a different kind of bulb? You will need to see the socket available at the back of the headlight.

Removing the old bulb or stock bulb out of the headlight will reveal the back of the headlight.

To use a 9003 bulb, you will need three wires coming out of the headlight’s base, which will suit the three prongs featured by the bulb.

If this is possible, you will save money as you’ll need only one 9003 bulbs to light the high beam and low beam.

Some H4 & 9003 Headlight Bulbs We Recommend

01. Philips 9003B1

 

 

Highlighted Features

  • Original halogen bulbs from Philips made in Germany
  • Headlight bulbs should be changed in pairs to have the same beam effect on each headlight
  • 45 watts 9003 halogen headlight bulbs
  • Compliant with DOT standards

The pack contains one halogen bulb from Philips. The recommendation is to buy two bulbs when looking to replace the old bulbs from the car’s headlights.

This will ensure the same level of light on both headlights, considering that halogen bulbs will gradually dim in time.

Each bulb will have 45 watts, but even so, the output light will be bright.

After installing the bulbs, make sure the headlights are not aiming too high, as the light could affect other drivers.

Pros

  • Very bright 9003 halogen bulbs for the price tag

Cons

  • Choose the bulb carefully, as it doesn’t fit all cars

02. SEALIGHT H4/9003/HB2

 

 

Highlighted Features

  • A combo kit consisting of two 9003 LED headlight bulbs
  • Provides a brighter light and improved beam compared to halogen lights
  • The beam is focused on the road, being safe for other drivers
  • A silent, fanless design keeps the bulbs cool while in use

An LED headlight bulb will be brighter and will offer longer hours of light, without dimming, compared to halogen bulbs.

The beam is improved and will target the road without blinding other drivers. It will also be wider, improving visibility on the side of the road.

Pros

  • Great customer service
  • Easy installation

Cons

  • The bulbs won’t work properly on all cars

03. Osram Night Breaker Laser H4

 

 

Highlighted Features

  • Halogen headlight bulbs that are 150% brighter;
  • The bulbs provide the light that is 20% lighter;
  • The long beam can go as far as 150 meters on the road;
  • Duo box that offers two light bulbs in one single package;

These are halogen bulbs, not LEDs, but they are brighter than regular halogen or stock bulbs.

The provided light is whiter and brighter and the beam goes further down the road, allowing drivers to see up to 150 meters in the dark.

Pros

  • Could be better than LED bulbs, providing an even light without dark spots
  • A noticeable upgrade from stock halogen bulbs

Cons

  • May not be as bright as one expects

04. AUXITO H4 9003 HB2

 

 

Highlighted Features

  • Easy-to-install LED headlight bulbs that work for 95% of the cars
  • The beam is aimed at the road, not blinding other drivers
  • Each bulb mounted will provide 4500 lumens
  • The cooling design is fanless for a silent functioning

LED headlight bulbs are an excellent choice when you need a white light on the road, at night.

This product has a fanless design, which means no noise is emitted when the bulbs are on.

Even so, the cooling is done effectively, allowing the bulbs to offer thousands of hours of light.

Pros

  • In most cases, no modifications are required to mount the bulbs
  • Bright white light and improved visibility

Cons

  • Patience may be required when installing the bulbs since it takes a while to get them properly aligned

05. Sylvania 9003XV.BP2

 

 

Highlighted Features

  • It provides a longer beam down the road with no glare
  • Legal and safe design, suitable to be used on public roads
  • It is recommended to change bulbs in pairs, as halogen bulbs dim in time
  • An improved version compared to regular Sylvania bulbs

This product from Sylvania is an improvement compared to other bulbs they sell since it is brighter.

Also, the beam is longer and more directed on the road, while the color of the light is also better.

The purpose of this product is to offer drivers improved visibility at night.

Pros

  • Accessible option, brighter than some halogen bulbs on the market
  • Improved beam and color of the light

Cons

  • They won’t last for too long since they are halogen bulbs

06. Fahren H4/9003/HB2

 

 

Highlighted Features

  • Premium LED headlight bulbs that are three times brighter than halogen bulbs
  • Quick installation, due to design similar to halogen bulbs
  • Bulbs are CANbus ready, being compatible with 98% of car models
  • Effective cooling fan for 50,000 hours of light

Extremely bright LED lights with an adjustable beam. Rotating the beam to 360 degrees is possible until the best results are obtained.

The bulb’s body is made of military-grade aluminum, ensuring resilience to wear and various driving conditions.

Water, dust, dirt, and snow will not cause any issues and driving will be safe all year round.

Pros

  • The provided light is very bright and will improve visibility on the road
  • The beam goes a long way

Cons

  • The bulbs might get rather hot after being in use for a while

07. BEAMTECH H4 LED Bulb

 

 

Highlighted Features

  • Double-sided LED chips, which produced an outstanding light output
  • Long lifespan, as the product can offer up to 30,000 hours of light
  • The temperature of the bulbs is kept low for an extended time of usage
  • Fanless design and easy installation

Silent, plug-and-play headlight bulbs that are ready to use right away. Some cars may need a decoder to use the benefits of this product.

The provided light is of a bright white and the high-quality aluminum body will keep the bulb cool during use.

Pros

  • Bright white light and focused beam on the road
  • “Plug and play” design

Cons

  • They don’t work properly on all car models

08. HELLA H4P50TB

 

 

Highlighted Features

  • The package contains two headlight bulbs
  • Halogen bulbs provide 50% more light than regular bulbs
  • The filament design has been improved and silver coating added to minimize the presence of the bulb in the headlight
  • It is recommended to replace bulbs in both headlights at once

Hella provides a set of two halogen headlight bulbs, which are easy to mount and use.

Compared to other halogen bulbs, this product offers 50% more light.

The bulb’s filament and aspect were also improved to be more discreet inside the headlight.

Pros

  • A brighter light on the road, better spotting of obstacles
  • Easy and convenient installation

Cons

  • Halogen bulbs will gradually dim in time

09. Hikari H4/9003 20000LM

 

 

Highlighted Features

  • LED headlight bulbs that provide a bright white light
  • The bulbs are four times brighter and go twice as far as regular halogen bulbs
  • Crisp color and focused beam for better driving at night
  • Design similar to halogen lights, for easy replacement

The product is equipped with high-quality chips that provide brighter light for a higher number of hours.

Due to the focused beam, it becomes safer & comfortable at night. The brightness of the light will not blind other drivers.

The bulb is protected against water, dust, and debris, which will prolong its lifespan.

Pros

  • Brighter and wider beam
  • Protection against water and dust

Cons

  • Not the best customer care services

People Also Search For

01. Are 9003 and H4 The Same Kind of Bulbs?

9003 bulbs are similar to H4 bulbs since both feature two filaments and can be used for both the low and high beams.

However, they are used differently and, at the same time, there are differences regarding their base (with implications on how they must be mounted).

H4 bulbs are not legal to be used by cars on public roads since they are very bright and might blind other drivers. Thus, they are mainly used by motorcycles.

9003 bulbs, on the other hand, are legal and can be used on public roads if the car is compatible with a double filament headlight bulb.

02. Are 9003 and H4 Bulbs Interchangeable?

As mentioned earlier, 9003 and H4 bulbs have different base designs. Thus, because of their different fitting, they are not interchangeable.

For example, if you have a car requiring 9003 bulbs, you can install only 9003 bulbs or HB2 bulbs, which are the same.

It will be impossible to install H4 bulbs, only with difficulty and if certain modifications are made.

03. What is The Difference Between 9003 and H4 Bulbs?

Despite similarities, 9003 and H4 bulbs emit different beams. Thus, even if they would be interchangeable, the emitted light would be different.

This is because 9004 bulbs feature a transverse filament, while H4 bulbs feature longitudinal filaments.

Another difference can be seen when closely inspecting their bases.

9003 bulbs have three prongs of equal size, while H4 bulbs have one of the three prongs larger than the rest.

This is why replacing 9003 bulbs with H4 bulbs is impossible.

04. Is 9003 The Same as HB2?

HB2 is just another name used for 9003 bulbs.

So, if you’re looking for a 9003 bulb and find an HB2 bulb, it’s good to know they are the same.

Final Thoughts

In case your car is compatible with headlight bulbs that feature two filaments and three prongs in the base (meaning that three wires are coming out from the back of the headlights), 9003 bulbs are the best choice.

H4 bulbs appeared in Europe for sports cars and can still be seen on some European cars.

But, in the US, the H4 bulbs are illegal and are used mostly on motorcycles since the law doesn’t require motorcycles to use sealed beam headlights.

A safer and more durable option for cars, driving on public roads, represents 9003 bulbs.

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