Curious about the differences between H11, H8, H9, and H16 bulbs? Or confused by bulbs listed as “H9/H11” or “H8/H11”? This guide got you covered.

If you are in a rush, here are the key takeaways:

The sockets and connectors of H11, H8, H9, and H16 are nearly identical, making them easily interchangeable with each other. However, the H11, H8, H9, and H16 halogens have different wattages, lumens, and slightly different dimensions optimized for their intended uses. (The later section will cover these details).

For LED upgrades, most H11 LED bulbs are universal. Aftermarket LEDs are engineered to directly replace H8, H9, H11 and H16 halogen equivalents. For example, SEALIGHT offers combined LED lines like H11/H9/H8 LED headlight bulbs and H11/H8/H16 LED fog lights.

So if your halogen is an H9, SEALIGHT's H11/H9/H8 LEDs will fit right in.

What Are the Differences And Similarities of H11, H8, H9, and H16

The Similarites

Shape and connectors:

H9, H11, and H8 and H16 have the same connector since they are the same bulb with the exact same plug. As pictured above, it consists of two narrow-set prongs enclosed in a plastic oval casing with a plastic divider at the center and two tabs on either end of the casing.

It is characterized by having a traditional right-angled style connector input base, a large rubber o-ring below the metal tabs, and 3 metal tabs spaced evenly apart around the base to lock it in place.

Filament:

All are single filament bulbs.

Voltage:

All three are rated 12 volts. Most automotive headlights and fog light bulbs are.

Lighting Technology:

H11, H8, H9, and H16 are available in halogen, LED and HID lighting technology. They always come in standard halogen bulbs from the factory, but they can all upgrade to LED or HID bulbs.

The Differences Between H11, H8, H9, and H16

Although the bulbs are physically interchangeable, you should know that the halogen types of H11, H8, H9, and H16, have some different technical metrics. Let’s break it down:

Wattage:

The main difference between these bulbs is the wattage, with H16 having the lowest wattage at 19 watts, H9 at 65 watts, H11 at 55 watts, and H8 at 35 watts.

Applications/Position:

H11 is the most common of the three, using 55 watts and found in low beam headlights and can also be used as fog lights. H9 is usually found in high beams and uses 65 watts. H8 is used for fog lights and uses 35 watts. and the H16 is also usually placed in fog light applications.

Brightness:

The standard H8 halogen bulb has 800 lumens, H9 is 2100, H11 is 1350, H16 is 500 lumens. Note that the exact number may vary depending on the manufacturer.

If you opt for LED headlight bulbs, the lumens will go higher as LED headlight bulbs are much brighter. For example, at SEALIGHT, the H11/H9/H8 headlight bulb lumens range from 14000 to 28000 lumens.

Lifespan:

Average Life of the basic halogen bulb: The H8 has a life of 320 hours, the H9 has 240 hours, the H11 has 270 hours, and the H16 has the shortest lifespan at 150 hours.

Note that the lifespan of the headlight bulbs also depends on many factors. One major consideration is the use frequency of the bulb. If the H11 bulb is used as low beam and H9 is for high beam, then H9 will last longer since lower beams are used less often.

Also read: H11 Headlight Bulb Guide: Things to Know & Best LED Options

H11 vs. H8 H9 H16, Are They Interchangeable?

When shopping for LED headlight bulbs, you'll often see H11, H8, H9, and H16 listed together as options. This can create confusion about which bulb sizes can be used interchangeably. Here's a breakdown of how these common headlight bulb types compare:

H11 vs. H8

The H11 and H8 bulbs have identical dimensions and connectors, making them interchangeable in most vehicles. H11 bulbs operate at 55 watts, producing brighter output often used in headlights. H8 bulbs run at just 35 watts with lower light output, typically used in fog lights.

H11 vs. H9

The H11 and H9 share the same physical design and can be swapped in most applications. The key difference is power draw and intended use. H11 bulbs pull 55 watts for low beams, while H9 bulbs draw 65 watts for high beams.

H11 vs. H16

The L-shaped H16 is essentially an H11 bulb that operates at lower wattage. They are interchangeable, with H11 used for low beams and H16 for fog lights.

More information about H16 Bulbs:

You may find that the H16 bulb comes in two styles: L-shape and T-shape. Only the L-shape style is interchangeable with H11, H9, and H8 bulbs.

The original H16 bulb design is L-shape. Most OEM bulbs labeled as H16 from brands like Sylvania or Philips use this L-shape design. It is part of the H9/H11 bulb family.

However, in recent years, some manufacturers have made a new version of the H16 bulb that uses a T-shape design. This newer T-shape H16 is equivalent to bulb numbers 5202, 2504, PSX24W, PS24W, 5201, and 9009. It is not interchangeable with the original L-shape H16 bulbs.

So in short:

H8 = Interchangeable with H11, lower output for fog lights

H9 = Interchangeable with H11, higher output for high beams

H16 (L-shaped) = Interchangeable with H11, lower output fog light

H11 vs. H8 vs. H9 vs. H16 Bulbs: Comparison Table

Which Bulb Fits My Car? H11, H9, or H8?

The most accurate way to confirm your bulb size is to remove your existing bulb and check the number printed on its base.

You can also consult your owner’s manual, which specifies the correct bulb type for each light position.

Don’t Swap H8 for H11 Halogen Without Checking

H8 and H11 halogen bulbs may look similar, but they’re not always safe to interchange. The H8 is rated at 35 watts, while the H11 runs at 55 watts. That extra power means extra heat, and in vehicles that use H8 for fog lights (like the 2012 Kia Optima), too much heat can melt the plastic housing or damage the wiring. Always check your vehicle's specs before using a higher-wattage bulb.

Want Whiter or Brighter Light? Go LED Instead

If you're after a cooler, whiter glow — the kind that gives your car a more modern look — LED bulbs are a much safer upgrade. They use less power than even the lower-wattage H8 halogen, usually around 32–35 watts, and they produce far less heat. That makes them a great fit for assemblies originally designed for halogens.

Replacing or Upgrading: What to Know

For halogen replacements, match the original bulb exactly, for example, replace an H9 with another H9.

For LED upgrades, manufacturers often design bulbs to be compatible across H8, H9, and H11 sockets. That’s why an H11 LED headlight bulb may work in a car that originally uses an H8 or H9 bulb.

For fog lights, it’s common to replace an H8 halogen with an LED labeled for H11/H8/H16 use.

Remember: Always verify which bulb fits your particular vehicle before purchasing. Getting the size right matters.

What’s Next

Now that you know the differences between H11, H9, H8, and H16 bulbs, the next step is choosing the right upgrade.

If you often drive off-road, upgrading to SEALIGHT H11 LED headlight bulbs or H11 LED fog light bulbs is definitely the best choice. They deliver much brighter illumination and last significantly longer than halogens.

Below are some of the most popular SEALIGHT LED options we recommend:

If you need to replace H11 headlight bulbs, check these:

-13%

Sealight^®

S2 H11/H9/H8 60W 6500K White IP68 LED Headlight Bulbs 2Pcs

4.75 star rating

(914)

Sealight^®

S1 H11/H9/H8 60W 6000K White IP67 LED Headlight Bulbs 2Pcs

4.73 star rating

(22)

For H11 fog lights, check these:

-20%

Sealight^®

XF3 H11/H16/H8/H9 LED Fog Light Bulbs 6500K White 60W 12000LM IP68 2PCS

4.88 star rating

(49)

-18%

Sealight^®

F1 H11/H16/H8/H9 LED Fog Light Bulbs 6000K White 20W 6000LM IP67 2PCS

4.64 star rating

(161)

You can enter your car's year, make and model to confirm if the LED bulbs are fit for your ride. Plus, we offer free shipping and 90-day returns for a hassle-free purchase.

Make the switch to SEALIGHT LEDs today!

Have questions or experiences to share about upgrading your headlights? Leave a comment below — we’d love to hear from you!