Knowledge Base

How Many Watts Does a Lamp Use? (Power Consumption Test)

By:Michael Johns

lamp power header

On this page, you will find out how many watts a lamp draws.

Lighting is one of the most practical uses of electricity. Thomas Edison’s invention of the light bulb makes him one of the most famous people to have ever lived. 

Nowadays it is something we take for granted until there is a power outage at least! At the flick of a switch, we can turn lamps on and off around the home. You can even get wifi smart bulbs now to manage from your smartphone. One thing you should keep your eye on is the power consumption of a lamp.

Below we will discuss and test lamp wattage, explain how to work it out for yourself, and calculate the total electricity required.

How Many Watts is a Lamp?

The average lamp uses between 30 and 60 watts. Although, if you are using LED bulbs a lamp will use about 6 to 11 watts.

The exact number depends on the size of your lamp and the lightbulb you use. For example, you might use a lower lumen light bulb which only draws 30W. While you might also have brighter lamps using a 60W light bulb.

As you can see there are a couple of things to consider here.

Firstly, the light bulb is what determines the power consumption. Bulbs come in many different wattages. For traditional incandescent bulbs the most common are 30W, 40W, and 60W.

You can also now buy LED light bulbs. These are much more efficient and provide more light at a lower wattage. The most common size LED bulbs are 6W, 8W, 11W. These are 80% more efficient, to give you an idea an 11W LED bulb is the same brightness as an incandescent 60W bulb. (And yes, you can use LED light bulbs in any lamps!)

The second thing to consider is the power rating of the lamp. You should not use a more powerful light bulb than the lamp is designed for. E.g. don’t use a 60W bulb in a 30W rated lamp. This information should be noted on the appliance. 

How to Find Out Your Lamp Wattage

There’s 3 ways you can work out the wattage of a lamp.

  1. Check Product Specification

The quickest way is to look at the lamp’s light bulb specification. The watts (W) is usually written on the glass. If not, you can check the user manual or the manufacturer’s website for technical details.

lamp power spec
  1. Use a Wattmeter

A wattmeter is brilliant for getting a live wattage reading and tracking total energy usage of any appliance. You can plug it into your lamp to get instant information. 

I used one to test my lamp with an incandescent Edison bulb which gave a live reading of 46.4W.

Lamp watt test showing 46.4W

Next, I tested the same lamp with an LED light bulb at it showed a reading of 9.7W.

Lamp led watt test showing 9.7W
  1. Wattage Formula or Calculator

If you know the amperage and voltage of your lamp you can use this to find the maximum watt rating. Simply use the formula Amps x Volts = Watts. Or you can head over to the ‘Watt Calculator’ to work this out.

Lamp and Bulb Wattage Examples

Let’s take a look at specific examples of how many watts a lamp draws. Below is a collection of modern lamps with their listed power ratings.

BulbPower Rating (Watts)
Westinghouse Lighting FrostedBulb30
Philips 223131 R20 DuraMax30
GE Chandelier Light Bulb40
Edison Light Bulbs Vintage Incandescent60
GU10 BulbsHalogen GU1050
SYLVANIA Halogen Double Life A1972
LEKE E26 LED Bulb 80W-100W Equivalent8
Linkind A19 LED 60W Equivalent  Light Bulb9

As you can see, the power ratings vary between different lamps. So you should take the time to check your own appliance.

How Much Electricity Does a Lamp Use?

You can use lamp wattage to work out how much electricity it uses. Plus this can be useful in understanding how much it costs to run your lamp.

A watt (W) is a measurement of power at a single point in time. A watt-hour (Wh) is the total amount of electricity used in an hour. For example, a lamp drawing 60W would use 60Wh when running for an hour.

Happily, electricity bills are recorded in kilowatt-hours (kWh). A kilowatt is simply 1000 watts. So a 60W lamp running for 1 hour uses 0.06kWh.

In reality, you use a lamp for 5 hours a day. This means a 60W lamp uses about 300Wh or 0.3kWh electricity a day. That’s 9kWh a month and 109.5kWh a year. 

That’s a rough electricity cost of $1.35 a month or $16.42 a year to run a 60W lamp for 5 hours a day. 

This number is based on using a traditional incandescent bulb. If you switch your lamp light bulb to an equivalent LED bulb it would cost just $3 for a year!

Using a Lamp Off-Grid

Planning to use your lamp in an off-grid situation like a power outage, RV, boat, semi-truck, or similar? The information above is important. You can ensure your electrical equipment offers enough power and calculate the run time.

You can either use a power inverter, portable power station, or generator to generate AC electricity. 

To make sure everything runs smoothly you should check two things on this equipment – wattage capacity and total energy capacity. 

Your power source, like an inverter, should have a wattage capacity of at least 20% more than your lamp. This ensures it will be able to deliver enough power as they are never 100% efficient. 

Secondly, you need to ensure your energy source, like a battery, has enough energy to run the lamp for the required amount of time. As we already know a normal light bulb and lamp can use 60Wh electricity per hour. This is the equivalent to 5Ah on a 12V battery.

Once again, consider changing to an LED light bulb to cut this figure by 80%! Remember, you can use an LED light bulb in any lamp.

How Many Watts Does a Lamp Use Summary

I hope you now have a clear understanding of how many watts a lamp uses.

As you have discovered, the power consumption of a lamp is directly related to the bulb you are using. If you have a traditional lightbulb this is likely to be between 30W and 60. But more and more people are switching to LED equivalents to reduce wattage by 80% to 11W or less. This switch helps to reduce total electricity usage and run for longer when using off-grid energy supplies like batteries.