Automotive Bulb Types Guide

Modern vehicles use a variety of bulb types depending on the application — from powerful headlights to small interior and instrument panel lights. This guide covers the most common automotive bulb types to help you understand what's used in your vehicle and find the right replacement.

Halogen Bulbs

Halogen bulbs are the most common type found in modern vehicles. They use a tungsten filament surrounded by halogen gas, which extends bulb life and improves brightness compared to standard incandescent bulbs.

Single-Beam Headlight Bulbs

Single-beam bulbs are used for dedicated headlight functions — one bulb per beam (low or high). They are also commonly found in fog lights.

H1, H3 — older single-beam types, found in fog lights and older headlight designs. H2 is less common and appears mostly in older European vehicles.

H7, H8, H9, H11, H11B, H15, H16 — modern single-beam bulbs widely used for low beam, high beam and fog light applications. H15 is a unique type that combines high beam with a daytime running light function in a single bulb.

Dual-Beam Headlight Bulbs

Dual-beam bulbs handle both low and high beam using two filaments inside one bulb. They are used in headlight assemblies that have only one bulb per side, which is common in trucks, SUVs and older passenger cars.

H4 (also sold as 9003), H13 (also sold as 9008), 9004, and 9007 are the main dual-beam types. The H4/9003 and H13/9008 pairs are physically identical bulbs — they are simply labeled differently depending on the ECE or SAE standard used by the manufacturer.

Fog Light and DRL Bulbs

In addition to H-series bulbs listed above, the following 800/900-series bulbs are widely used in fog lights and daytime running lights across North American vehicles: 880, 881, 885, 886, 889, 890, 891, 893, 894, 896, 898, 899. Related types 9040, 9045, 9055, 9140, 9145 are also used in fog light positions. 5201, 5202 and PSX24W are found in newer vehicles with dedicated fog light sockets.

Headlight-Only 9000-Series

These are single-beam headlight bulbs commonly used in North American-market vehicles: 9005 (high beam), 9006 (low beam), 9011, and 9012. The 9005XS and 9006XS variants have a shorter body designed for compact headlight housings.

Motorcycle Headlight Bulb

HS1 is specifically designed for motorcycle headlights. It is physically similar to the H4 but with lower wattage to suit motorcycle electrical systems.

HID / Xenon Bulbs

HID (High-Intensity Discharge) bulbs produce light by creating an electric arc between two electrodes inside a capsule filled with xenon gas and metal salts. They are significantly brighter than halogen bulbs, have a longer lifespan, and produce a distinctive white-blue light. HID bulbs require a ballast unit to operate.

D1S, D1R — first-generation HID bulbs with an integrated igniter. Found in luxury vehicles from the early 2000s.

D2S, D2R — the most common HID type, widely used in Japanese and European vehicles.

D3S — a mercury-free version of D1S, introduced for environmental compliance.

D4S, D4R — mercury-free versions of D2S/D2R, very common in Toyota and Lexus vehicles.

D5S — a compact, low-power HID bulb used in smaller projector housings.

The letter suffix indicates the housing type: S = projector lens (smooth, clear outer glass), R = reflector housing (opaque shield with a cutoff pattern etched into the bulb itself).

Standard Incandescent Bulbs

These are traditional bulbs with a glowing tungsten filament. They are the workhorses of automotive lighting — used for turn signals, brake lights, tail lights, reverse lights, and interior lighting across most vehicles.

Dual-Filament Bulbs (Stop / Tail / Turn)

Dual-filament bulbs have two filaments: a brighter one for braking or turn signals, and a dimmer one for tail or parking lights. They are among the most common bulbs in North American vehicles.

Standard types: 1157, 2057, 1034, 3157, 3057, 7443, 7444, 2357, 2355, 2356, 4157, 4057, 1004, 1154, 1158, 1159.

Natural Amber variants: 1157NA, 3157NA, 3057NA, 7443NA, 7444NA, 1034NA, 2057NA, 2357NA, 4157NA, 4257NA.

Single-Filament Bulbs (Backup / Turn / Reverse)

Single-filament bulbs have one filament and one brightness level. They are used for backup lights, single-function turn signals, and various marker lights.

Standard types: 1156, 1141, 1073, 1129, 1003, 7440, 7441, 3156, 3155, 921, 912, 906, 916, 917, 920, 922, 904, 1076, 1142, 1155.

Natural Amber variants: 1156NA, 7440NA, 3156NA, 916NA.

Signal and Marker Bulbs (Bayonet Base)

Smaller bayonet-base bulbs (BA9s and similar) used for various signal, marker, and courtesy light functions: 57, 53, 63, 67, 68, 89, 90, 93, 97, 81, 51, 70, 105, 1445, 1816, 1889, 1891, 1892, 1893, 1895, 1896, 257, 330, 631.

About the NA Suffix

Bulbs with the NA suffix (Natural Amber) have orange-tinted glass built into the bulb, providing amber light output without relying on a colored lens. They are required in many applications where turn signal indicators must appear amber even through a clear lens.

European Standard Bulbs (ECE)

These bulbs follow ECE (European) regulations and are standard on European-market vehicles. Many modern globally-sold vehicles use these types as well.

Signal and Brake Bulbs

P21W — a single-filament bulb and the European standard for brake lights, reverse lights and turn signals. Very widely used globally.

P21/5W — a dual-filament version combining stop and tail light functions in one bulb.

P21/4W — an asymmetric dual-filament variant for combined functions where different brightness levels are needed.

PY21W — the amber-glass version of P21W, required for turn signals that are not behind an amber lens.

PY24WNA — an amber signal bulb found in some newer European vehicles.

Auxiliary European Types

Additional ECE-standard bulbs used for parking, side marker, indicator repeater, license plate and daytime running lights: WT21W (W21W), WT21/7W (W21/7W), H21W, H6W, and R5W (also numbered as 12821).

Philips-Numbered European Bulbs

Philips assigns unique catalog numbers to many ECE bulbs. These are the same physical bulbs described above, sold under Philips part numbering. You may encounter these numbers in European-market vehicle owner manuals: 12088, 12174NA, 12174SV, 12177, 12180, 12182, 12184, 12185, 12188, 12271NA, 12272NA, 12274NA, 12275, 12277, 12278, 12496, 12821, 12961, 13050, 17053.

Festoon (Tube-Shaped) Bulbs

Festoon bulbs are small cylindrical (tube-shaped) bulbs with contacts on both ends. They are primarily used for dome lights, map lights, vanity mirror lights, license plate lights and trunk lights. Different lengths are not interchangeable — always match the correct millimeter size when replacing.

DE-Series Festoon

The DE prefix designates festoon bulbs by their approximate length in millimeters: DE3021, DE3022, DE3175, DE3423, DE3425 (all approximately 31mm), and 6428 (also 31mm).

Numbered Festoon

These use traditional part numbers instead of the DE prefix. The approximate length in millimeters: 6461 (~29mm); 6411, SE1274 (~36–39mm); 211-2, 212-2, 214-2, 561, 562, 578, 579 (~41–44mm).

Miniature Wedge and Instrument Panel Bulbs

Small wedge-base bulbs used for parking lights, side markers, courtesy lights, license plate lights and instrument panel indicators. The wedge base simply pushes into the socket without twisting.

T10 Wedge (Standard Size)

The most common miniature automotive bulbs, used across a huge range of parking, side marker, license plate and courtesy light applications: 194, 168, 158, 192, 193, 161, 2721, 2723. Amber variants: 194NA, 168NA.

Instrument Panel Bulbs (T5 and Smaller)

Very small bulbs that illuminate dashboard gauges, HVAC controls and indicator lights: 74, 37, 73, 24, 94, 70. Amber variant: 24NA.

Sealed Beam Headlights

Sealed beam headlights are self-contained units where the lens, reflector and filament are permanently assembled into one piece. When the filament burns out, you replace the entire unit. These were standard on all US-market vehicles until 1983 and remain common on older trucks, Jeeps and classic cars.

Round Sealed Beams

Available in 7-inch and 5¾-inch diameter sizes: H6024 (7" round), H6006 (7" round, low beam), H5001 (5¾" round, high beam), H5006 (5¾" round, low beam).

Rectangular Sealed Beams

Used in vehicles from the late 1970s through the mid-1990s with rectangular headlight openings: H6054 (large rectangular), H4651, H4652, H4656, H4666, H4701, H4703, H4351, H4352 (small rectangular).

Specialty and Painted Cap (PC) Bulbs

Painted-cap (PC) bulbs have part of their glass coated with an opaque paint to block light in specific directions, preventing glare or light leakage in tight housings. They are direct replacements for their non-PC counterparts but with controlled light output: PC168, PC194, PC195, PC175, PC161, PC74, PC37, PC579.

Other Specialty Types

Various application-specific bulbs that don't fit neatly into other categories: 199, 198, 232, 2040, 2397, 2456, 2458, 3456, 3457, 3496, 3497, 3893, 5008, 5702AK. Amber variants: 3457NA, 3357NA, 3757NA.

LED Replacements

Most bulb types in this guide have direct LED equivalents available on the aftermarket. LED bulbs offer significantly longer lifespan, lower power consumption, faster response time (especially important for brake lights) and instant-on behavior without warm-up delay.

However, some applications — particularly turn signals — may require a load resistor or CANbus-compatible LED to avoid hyper-flashing or dashboard error messages. This happens because the vehicle's flasher relay detects the lower power draw of an LED and interprets it as a burnt-out bulb. Interior and license plate lights typically work as drop-in replacements without any modifications.

Common Bulb Number Suffixes

Automotive bulb part numbers often include letter suffixes that indicate a specific variant of the base bulb type: