If you drive in fog quite regularly, the choice between yellow and white fog lights is not cosmetic. It has a direct impact on visibility and driver fatigue, especially in regions such as Delhi-NCR, where winter fog often reduces visibility to a few metres and contributes to frequent multi-vehicle accidents.
What fog lights are designed to do
Fog lights are mounted low and aimed downward to illuminate the road surface close to the vehicle. Their purpose is not to throw light far ahead, but to help the driver see lane markings, road edges and obstacles without excessive glare reflecting back from fog, rain or dust.
How do yellow fog lights behave in thick fog?
Yellow fog lights use light with a longer wavelength compared to white or bluish light. In real-world terms, this means the light scatters less when it hits fog or heavy moisture in the air.
In dense fog conditions, this reduced scatter can improve contrast, making lane markings, kerbs and road edges slightly easier to pick out. Yellow light also tends to produce less glare, both for the driver and for oncoming traffic. This is one reason why yellow fog lamps were historically common on European vehicles designed for poor weather conditions.
The trade-off is brightness. Yellow fog lights illuminate a smaller area and do not light up the road as vividly as white lights. They are most effective when visibility is severely compromised.
Where white fog lights make more sense
White fog lights are brighter and closer to the natural daylight spectrum. They illuminate a wider area and offer better clarity when conditions are only moderately bad, such as light fog, mist, rain or dust.
In these situations, white fog lights help drivers see more detail on the road surface and slightly farther ahead. This is why most modern cars sold in India come with white fog lamps from the factory.
However, in very thick fog, white light can reflect back more strongly, increasing glare and sometimes reducing usable visibility rather than improving it.
(Also Read: Low visibility driving tips: How to drive safely in heavy fog)
Which one should you use if you drive in fog often?
For drivers who frequently encounter dense fog, such as early-morning highway runs around Delhi-NCR in winter, yellow fog lights can offer a practical advantage by reducing glare and improving contrast close to the vehicle.
If your driving involves a mix of light fog, haze and rain rather than consistently thick fog, white fog lights remain the more versatile and practical option.
There is no universal best choice. The decision should be based on how severe the fog usually is where you drive, not on appearance or trends.