How Many Amps Do LED Headlights Draw?

You should learn about the amp draw of an LED headlight for many reasons.

Firstly, if you ever blow a fuse for your headlights, you’ll need to ensure that you get a suitable one to replace it.

Plus, some people – more motorcycle drivers – may look to convert a single halogen headlight into dual LEDs without making any changes to the fuse.

LED headlights don’t draw many amps – typically just over 2 amps for low beam, although some bulbs draw a lot more. You can calculate the amps drawn by dividing the wattage of the bulb by the voltage of the battery, which in cars and motorcycles is 12 volts.

Because it’s useful to understand the amperage of your headlights, let’s take a look at:

• How LEDs compare to halogen headlights
• How to convert watts to amps
• The maximum amperage that LED headlights can handle

LED vs Halogen Headlights Amp Draw

It’s difficult to accurately compare LED and halogen headlights in terms of power draw because the LED headlight market is still emerging.

That means there isn’t a standard LED bulb in terms of wattage in headlights.

But the easiest way to compare is to take the lowest wattage LED bulbs being used, which are generally 25-watt bulbs.

A 25-watt LED bulb draws just over 2 amps, but remember that when comparing this for cars, you need to double this since you have two headlights. So the total amps drawn by a pair of LED headlights are typically around 4.16 amps.

In comparison, older halogen headlight bulbs typically use 55 watts of power per bulb, so the total power drawn by the pair would be 9.16 amps.

How Do I Convert Watts To Amps?

Working out how many amps an electrical device draws is a straightforward equation.

All you need to do is divide the device’s wattage by the voltage of the power source.

Motorcycle and car batteries run using a 12-volt battery, so your power source is a constant 12.

So to calculate the amps drawn, just divide the wattage of the bulb by 12.

Examples:

• 30 watt LED bulb – 30/12 = 2.5 amps
• 50 watt LED bulb – 50/12 = 4.16 amps
• 60 watt LED bulb – 60/12 = 5 amps

You can use this calculation for other electrical devices, too. Just make sure you know the voltage of your power source.

What Amperage Can An LED Headlight Handle?

Now that we understand how many amps LED headlights can draw, we also need to consider how much they can handle.

Because electrical circuits aren’t clever enough to only send the required current to the bulbs – if only.

Instead, we regulate the current through the use of fuses. A fuse will limit how much current can be sent through a circuit.

Choose a fuse that’s too low, and your bulbs aren’t going to work.

But choose a fuse that’s too high, and you’re going to massively overload your LED bulbs, which will not only destroy them pretty quickly but could also become a fire hazard.

The issue is that most LED manufacturers don’t publish the maximum amperage that an LED can handle.

So the best thing to do is to calculate the amps drawn by your LED bulbs, add 20% as leeway, and choose the closest fuse size above that.

Again, let’s look at some examples:

50-watt LED headlights

These will consist of two 25-watt LED bulbs and, therefore, have a total power draw of 4.16 amps.

Add on 20% to allow for minor fluctuations = 4.16 * 1.2 = 4.992. So a 5 amp fuse would be best.

60-watt LED headlights

These will have two 30-watt LED bulbs and a total power draw of 5 amps.

5 * 1.2 = 6 amps with the extra 20% leeway.

The next fuse size available is 7.5 amps, so this would be the best choice.

200-watt LED headlights

A 200-watt LED headlight kit is designed for high beams with a total power draw of 16.6 amps.

Adding on 20%, that gives a total of 20.

So a 20 amp fuse would be best.

While this applies to LED headlights of all wattages, it’s especially worth pointing out that with 200-watt kits – you need to check the local laws on LED headlight legality.

Even though they are sold by official manufacturers and popular stores, the responsibility for legal road use always lies with the motorist.

Final Words

If you’re switching out halogen headlight bulbs for standard LEDs that don’t have a huge power draw, the chances are you don’t need to change the fuses.

But you should still check what you have installed.

After all, if you go from a set of high-powered halogens to low-powered LEDs, you could overload your lights, so you may want to downgrade the fuse rather than upgrade it.

Have you added LEDs to your car, and if so, have you had any problems? It might be worth checking the fuse you’re using.