W21/5W LED Bulbs

Best Brightest W21/5W LED Bulbs

Do you have W21/5W LED Bulbs in your car and want to replace them with newer, brighter bulbs? We have created this manual especially for you. Our vast experience in the automotive field enables us to select for you the best W21/5W LED Bulbs on the market.

In this manual, we have listed all the most important characteristics that are used when choosing W21/5W LED Bulbs: the power of the W21/5W LED Bulbs emitter (W), Luminous flux of W21/5W LED Bulbs (Lumens), and color temperature of W21/5W LED Bulbs (Kelvin).

The LEDs are most commonly installed in headlights, they can also be installed in fog lights. They are suitable for both reflector headlights and optics with a lens, they can be installed on any of your car. The light from the latest generation of W21/5W LED bulbs already outperforms that of xenon lamps.

W21/5W LED Bulbs Reviews

W21/5W LED Bulbs

W21/5W LED Bulbs

Best W21/5W LED Headlight Bulbs

Philips W21/5W LED car signaling Bulb

Philips W21/5W LED car signaling Bulb

Technical Details

  • Wattage 21 watts
  • Voltage 12 Volts
  • Type of Bulb LED



Technical Details

  • Type of Bulb LED
  • Wattage 72 watts
  • Voltage 12 Volts
  • Color Temperature 6000 Kelvin
  • Luminous Flux 2400 Lumen


KATUR 3157 LED Bulb

Technical Details

  • Type of Bulb LED
  • Wattage 7,8 watts
  • Voltage 12 to 24 Volts
  • Color Temperature 6500 Kelvin
  • Luminous Flux 1600 Lumen

How to choose W21/5W LED Bulbs?

When choosing W21/5W LED Bulbs for the car, you need to consider the type and socket of the lamp, bulbs power, bulbs temperature, manufacturer brand, and lamp life.

An important parameter when choosing W21/5W LED Bulbs is the light emitted by the bulb.

How bright and high quality the W21/5W LED Bulbs will depend on several factors:

  1. Power of the W21/5W LED Bulbs emitter
  2. Luminous flux of W21/5W LED Bulbs
  3. Color temperature of W21/5W LED Bulbs
  4. W21/5W LED Bulbs light directionality

W21/5W LED Bulbs

Power of the W21/5W LED Bulbs

The power rating of the W21/5W LED Bulbs is measured in watts (W) and is specified in the bulb datasheet.

Luminous flux of W21/5W LED Bulbs

The luminous flux of W21/5W LED Bulbs is the brightness of the beam emitted by the source. The brightness of the light beam is usually measured in lumens.

The 5000-6000 lumens (low intensity) lamps illuminate the road more than 500 meters in a straight line and are suitable for most drivers. At 8000 lumens (medium intensity) the road is illuminated for 600-700 meters in a straight line. Lamps with 10 000 – 12 000 lumens (high intensity) illuminate the road almost as well as daylight.

W21/5W Bulbs Color Temperature

The color temperature of an W21/5W halogen bulb is one of the most important characteristics that indicate the color emission of an automotive bulb. The luminous flux temperature is used to determine which color the lamp will glow.

The objective impression of the color of the W21/5W halogen bulb is determined by the color temperature measured in Kelvin. The table of colors and temperatures of W21/5W lamps come in different colors from yellow (3000K – 4300K), white (5000K – 6000K), to blue and magenta (8000K and more).

Color Temperature Bulbs

The color temperature of W21/5W LED lamps is about 2,800K, this warm-yellowish light is most familiar to the eye (2700 to 3500K). LED lights used in fog lights or headlights are in the 3000K range. HID lights start at 3000K and can reach up to 10,000K. Newer LED lights can have a luminous flux of up to 12,000K.

Color Color Temperature Description
Yellow 3000 K Pure natural yellow light
White 4300 K Yellowish white light (dim white light)
Pure White 5000 K Pure white light (imitates natural light)
Crystal White 6000 K Pure white light with a small amount of blue
Light Blue 8000 K Bluish-white light with a higher percentage of blue
Blue 10 000 K Dark blue light bordering on violet.
Violet 12 000 K Dark purple saturated light

Directionality of W21/5W LED Bulbs

The need to adjust the W21/5W LED Bulbs most often arises during the replacement of the lamp or during the long-term operation of the vehicle.

Due to driving on rough roads and constant vibration the geometry of the car headlights is disturbed. This leads to misdirection of the light flux and the risk of creating an accident on the road. Therefore, after the purchase of W21/5W LED Bulbs, it is necessary to adjust the lamp. W21/5W LED Bulbs are adjusted in height and direction, separately for each headlight.

If a headlight bulb burns out, should you replace two bulbs or one?

If you only replace the burned-out W21/5W LED Bulbs, the second bulb will eventually fail as well. Over time, the brightness of the W21/5W Halogen Bulbs drops, and the color temperature increases. Therefore, W21/5W LED Bulbs should only be replaced in pairs. Otherwise, driving will be uncomfortable because the new bulb will shine brighter than the old one.

W21/5W LED Bulbs Buying Guide

When buying W21/5W LED Bulbs, you need to pay attention to the cost of the lamp, the manufacturer, as well as the life of the W21/5W LED Bulb.

W21/5W LED Bulbs Manufacturers

We recommend that you do not save money when buying W21/5W LED Bulbs and choose proven brands that have proven themselves in the work. The best brands of W21/5W bulbs for cars according to our editorial board are Sylvania, Osram, Philips, Optilux Hella, Bosch.

Cost of W21/5W LED Bulbs

  • Up to 20 dollars: for this price you can buy good W21/5W LED Bulbs of little-known manufacturer
  • Up to $50: For this price, you can buy good W21/5W LED Bulbs from a well-known manufacturer
  • Up to $100: for this price, you can buy W21/5W LED Bulbs with improved brightness characteristics of the best lamp manufacturers

The lifespan of W21/5W LED Bulbs

A pretty important factor when choosing a W21/5W bulb is its lifespan. Choose W21/5W LED Bulbs that last longer than a year or two. This will save you from having to change W21/5W LED Bulbs very often and focus on the road.

The best bulbs on the market (Editor’s Choice):

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