When shopping for new headlight or fog light bulbs, whether replacing your stock halogens or looking to upgrade to a brighter alternative such as LED headlights, you will come across different bulbs for different beams.
In order to purchase the right product, it’s important to understand the different beams, when they are used, and their purpose. In short, the low beam is the primary source of light and most frequently used lighting function while the high beam is a secondary source of light used rarely in very dark settings such as on dark roads, the country, etc.
After reading this guide, you’ll understand the differences between low beams and high beams. We’ll also explain when you should use your low beams and high beams and conclude with some questions on this topic.
What Are Low Beams?
Low beams are the ‘normal’ lights your car headlights emit and are used when driving at night or in a dim or dark setting such as an indoor parking lot. Low beams have a short-range focus and are sometimes referred to as ‘dipped beams’.
Low beams are the most important and most frequently beam used in a car. The light beam is angled towards the ground in order to illuminate the road and to avoid blinding other drivers. They are a way for other drivers to see you.
Traditionally, drivers would have to manually turn on their low beams but newer cars do so automatically by detecting low light environments such as during the night or when entering a dim parking lot.
What are high beams?
The high beam headlight lighting function is normally activated in environments with little to no light such as the country or small roads with no street lights. High beams are sometimes referred to as ‘brights’ or ‘full beams’.
The light beam for high beams is angled upwards in order to illuminate a surface area above and beyond the light of the low beams. High beams have a long-range focus.
Unlike low beams, high beams will never turn on automatically. They must be manually turned on by the driver when needed. In fact, high beams should only be used for short periods of time when extra light is really needed.
Driving with your high beams can blind oncoming traffic, which can be very dangerous. Keeping them on for an extended period of time is illegal.
Dual-Beam Headlight Systems
All cars and trucks come with a low beam and a high beam function; however, some cars require two separate bulbs for each beam (single beam systems) while others require only one bulb (dual beam systems) for both.
Drivers that have cars with dual-beam systems will only need to buy one set of bulbs to replace (or upgrade) both low and high beams. Dual-beam bulbs are typically slightly more expensive than single beam bulbs and draw more power.
Difference Between Low and High Beam Headlights
The main difference between low and high beam headlights is that a low beam is used for normal nighttime driving, whereas high beams are used for driving in rural areas or small roads that feature little to no light.
A low or dipped beam is the projection of light in a lateral and/or downward fashion. Its main purpose is to provide adequate lighting without reducing your visibility of oncoming traffic.
However, when it comes to high or full beam lights, the light distribution is more centralized, allowing you to see a long stretch of the road. These lights are primarily used in poorly lit areas.
Low Beam vs High Beam Comparison:
| Comparison | High Beam | Low Beam |
| Beam Angle | Straight/Upwards | Towards the ground/road |
| Focus | Long-range | Short-range |
| Light Coverage | ~100 meters | ~40 meters |
| Best For | No light environments (rural areas, small roads, etc.) | Normal Nighttime driving / low light environments |
| Activation Period | Short period / as long as no other cars are within 150 meters | Must always stay on when in low or no light environment |
| Blind other drivers | Yes | No |
| Activation | Manual | Automatic or Manual |
| Legal | Yes | Yes |
| Halogen | Yes | Yes |
| LED | Yes | Yes |
| HID/Xenon | Yes | Yes |
Functionality
To ensure optimum effectiveness, both low and high beam lights have distinct functions based on the intensity and projection of light. The general rule is to engage low beams when the oncoming traffic is within a distance of 150 meters or around 500 ft.
People in well-lit city areas, where there is a healthy flow of traffic always use low beams. This prevents them from blinding oncoming drivers, ensuring a safer environment for everyone.
Contrary to popular belief, in extreme weather conditions like rain, fog or snowfall, one should switch to low beams. This is mainly because the water molecules reflect the light from high-beam headlights. That, in turn, would make it all the more difficult for drivers to have a clear view of the road. The water spots usually blur everything in front of you.
People tend to use high beams in rural areas or in the dark for better vision. Doing so will prevent you from blinding the driver in front of you due to the reflection in the rear-view mirror.
Advantages of these Modes
Depending on weather, brightness, and location, both modes have their advantages.
Low Beam Advantages
- Fewer accidents. Using low beams can ensure greater safety for oncoming traffic and of the vehicle in front of you.
- Ideal for extreme weather conditions. Be it rain, fog, or snow, you should use low beams in order to have better visibility of the road. The light particles won’t bounce off of the cloud particles and blind the driver.
- The civilized way to travel. The beam won’t cause strain on the eyes of pedestrians, cyclists and motorists alike.
High Beam Advantages
- Better visibility. Due to greater intensity in the projection of light, high beams are ideal in poorly lit areas or on deserted highways.
- Can be used as a signaling device. We can flash our high beams to warn people of the vehicle’s presence or to signal the right of passage.
- Curbing noise pollution. Flashing high beams at night, instead of using your horn, can reduce noise pollution.
Safety Measures
There are certain countries that have undertaken some additional measures to ensure the greater safety of on-road drivers.
For instance, left-hand traffic countries have introduced low-beam headlights that dip to the left. In contrast, right-hand traffic countries have low-beam lights that dip to the right. That way, drivers who are driving in the opposite direction from you aren’t blinded by your lights.
Some countries, like Canada, have also made it mandatory for every vehicle to be equipped with Daytime Running Lights. DRLs play a huge role when it comes to increasing visibility during the day. With higher visibility, the chances of road accidents diminish significantly.
However, one should bear in mind that DRLs do not activate tail lights. It is advisable to switch on low beams in times of extreme weather when the road conditions and visibility are poor.
Usage
Since they were first introduced in the early 1900s, headlights have changed quite a bit. Initially, they only used the Bilux bulb. Now, we have a wide variety of headlights to choose from, ranging from LEDs and halogen bulbs to Xenon HIDs, each with varying intensity and range of light.
But as they say, with power comes responsibility. If you use high beams, you can blind other drivers. That’s not only dangerous but also frustrating when it happens. You should operate your headlights accordingly. You need to be mindful of other drivers and create a healthy and safe driving experience.
Final Thoughts
Once upon a time drivers were required to get out of their car to switch between low and high beams. Now, one can achieve the same with the turn of a knob, nestled comfortably inside the car.
The world has changed significantly, and you are now able to take advantage of the latest automotive innovations. Something small like automatic headlights that turn on the moment they sense it dark outside serves as an additional safety feature in a vehicle.
Still, you should ensure the safety of your fellow travelers isn’t compromised due to your laziness. On-road driving is a team sport and we should strive to be team players.