White or Yellow? Which Headlight Color is Better? | SwiftlyParts

White or Yellow? Which Headlight Color Is Better?

The debate between yellow and white headlights has persisted among drivers for years. Some drivers firmly believe that yellow lights are ideal for improving visibility in adverse weather conditions. On the other hand, proponents of white lights argue that their brightness makes them superior.
In this article, we will examine the advantages and disadvantages of yellow and white headlights, and ascertain which option is superior for road usage.

Yellow headlights

Yellow headlight bulb on the passenger side of a white car

For decades, headlights were equipped with a yellow tint. The earliest headlights relied on acetylene lamps, which emitted a yellower light compared to the headlights we have today. As electric headlights gained popularity, the preference for yellow light emerged. During the 1930s, selective yellow light became prevalent in headlights. These lights were specifically designed to filter out blue tones, resulting in a yellower light. Studies conducted at that time indicated that yellow light was less dazzling to other drivers, making it a safer choice for headlights. Moreover, yellow light had the advantage of cutting through rain, snow, and fog more effectively than white or blue light.

While yellow headlights remained popular for many decades, most countries allowed for either yellow or white headlights, with the exception of France. From 1936 until 1993, French law required vehicles to have yellow headlights. Nowadays, most countries permit either white or yellow headlights. However, yellow lights have gradually lost popularity as primary headlights. Although yellow light improves visibility in wet or foggy conditions, it can hinder visibility in clear conditions. Consequently, modern vehicles often use yellow lights exclusively as fog lights.

White headlights

​Bright white headlight bulb on the passenger side of a silver car

White headlights have become the most popular choice for cars today. In numerous countries, regulations dictate that headlights must be white, prohibiting the use of yellow lights. This requirement is also seen in European regulations, which mandate white headlights for all newly manufactured vehicles.

The preference for white light stems from its ability to mimic sunlight, resulting in improved visibility. Unlike selective yellow light, which filters and dims the brightness of headlights, white light remains unfiltered and therefore brighter.

As headlight technology advances, some bulbs lean towards the blue end of the color spectrum, as opposed to yellow. Xenon HID bulbs, for example, are brighter than traditional halogen bulbs and often feature a blue tint. While this is acceptable to a certain extent, excessively blue headlights are less effective.

For optimal headlight color, pure white is the ideal choice. When looking for white headlight bulbs, it's crucial to take the color temperature into account. Halogen bulbs usually have a Kelvin rating of around 4000K, while xenon HID or LED bulbs have a rating of approximately 5500K, guaranteeing the brightest and whitest illumination possible.