How Many Watts Does a Space Heater Use? (Electric Space Heater Wattage)

The most common space heaters use 750 or 1500 watts, especially portable units. But low wattage personal space heaters start at about 200 watts. The largest space heaters are 20,000 watts.

Electric space heater wattage depends on the following:

  • The space heater model
  • The type of space heater

The wattage you see on the box is the amount the space heater consumes on its high setting. A 1,500-watt space heater, for example, will consume 1,500 watts only on its highest setting. The wattage drops when the setting is lowered, cutting the required run wattage in half (750 watts) when the heater is on its low wattage setting. 

How Many Watts Does a Space Heater Use? 

The following chart presents data on 269 of the most popular electric space heaters today. 

How Many Watts Does an Electric Space Heater Use:

Lowest Wattage200 W
Average Wattage1,600 W
Common Wattage1,500 W
Highest Wattage20,000W

Note: This data is based on 269 popular electric space heaters on the market.

The lowest wattage available is 200 watts. The average heater on the market is 1,600 watts, but most homeowners have 1,500-watt space heaters. 

Low wattage heaters, such as 200-, 500-, and 750-watts, are called personal space heaters since they are small, portable, and sit next to you. These heaters are most useful in table or desk spaces. 

1,500-to-4,000-watt heaters are best suited for heating entire rooms in the house. Use these in bedrooms, bathrooms, basements and other locations central heating doesn’t reach very well. 

Higher-wattage heaters, such as 5,000 to 10,000 watts, might help to warm up your garage, barn, or unheated areas less insulated against the cold.

The highest wattage heaters and electrical furnaces, such as those in the 15,000 to 20,000 watts class, are best suited for factories, schools, dormitories, and other large public spaces. Many are considered commercial space heaters. 

Space Heater Wattage of Different Heater Types 

There are various types of space heaters based on how they produce heat. 

Space Heater Wattage of Different Heater Types:

Heater TypeMin. WattageAverage WattageMax. Wattage
Ceramic Heater500 W1,360 W1,500 W
Infrared Heater1,000 W2,000 W6,000 W
Electric Fan Heater750 W1,300 W1,500 W
Radiant500 W1,200 W1,500 W
Forced Air200 W2,000 W20,000 W
Oil-Filled600 W1,360 W1,500 W

In order of high to low wattage:

Forced air: This type reaches up to 20,000 watts. It uses vents to transfer and direct heat.

Infrared: With a 6,000-watt maximum, infrared converts electricity into radiant heat.

Oil-filled: This type reaches a 1,500-watt maximum. It uses oil-covered electrical elements to generate heat. The purpose of the oil is to retain heat and keep radiating it once the space heater has been turned off.

Ceramic: With a 1,500-watt maximum, ceramic space heaters pass electric current through a ceramic-coated element. The ceramic boosts heat retention.

Fan (electric): This type maxes at 1,500 watts. It pushes cold air over a steel heating element to warm it up.

Radiant: This type reaches 1,500 watts and is similar to infrared. 

You will notice two patterns from our chart:

1 – Forced air and infrared space heaters have the widest wattage ranges, providing multiple product options—from personal heaters to industrial heaters.

2  – There is no major wattage difference among oil-filled, ceramic, fan, and radiant heater appliances.    

Space Heater Wattage of Different Brands 

The following chart presents a selection of the space heater brands you can find on the shelves with their wattage ranges.  

Space Heater Wattage of Different Brands:

BrandMin of Wattage Average of WattageMax of Wattage
Dr Infrared1,500 W1,500 W1,500 W
Vornado750 W1,260 W1,500 W
DeLonghi1,500 W1,500 W1,500 W
Pelonis1,500 W1,500 W1,500 W
Lasko200 W1,354 W1,500 W
Black Decker1,500 W1,500 W1,500 W
Comfort Zone1,000 W2,390 W7,500 W
Costway700 W1,453 W1,500 W
Heat Storm1,000 W1,714 W6,000 W
Hunter750 W1,125 W1,500 W
Mr. Heater1,500 W3,400 W5,300 W
Optimus700 W1,335 W1,500 W
Sharper Image750 W1,150 W1,500 W
Wexstar400 W600 W800 W

If you want low wattage space heaters, the two brands to look for are Lasko (200 watt) and Wexstar (400 watt). 

For high wattage heaters, the two brands to consider are Comfort Zone (7,500-watt maximum), and Heat Storm (6,000-watt maximum).

If the brands’ product maximums are too high for your preference, then know that each brand sells products that average 1,700 watts (Heat Storm) or 2,400 watts (Comfort Zone). 


1. Are all space heaters 1,500 watts? 

No, space heaters come in a range of wattage for most brands. 1,500-watt space heaters are simply a common find. 

2. Can you run a space heater with a generator? 

Yes, but you will need at least a 1,500-watt generator to properly run your heater. To be especially careful not to trip a circuit, use a 2,000-watt generator minimum. 

3. Do ceramic heaters use a lot of energy? 

No, ceramic heaters are known for being one of the more energy efficient types of space heaters. However, they are most efficient when used in smaller spaces, such as a bedroom or office.  

4. How do I know how much wattage I need to heat up a room? 

This is something you can only determine by calculating it. 

First, heating a room is measured in British Thermal Units, or BTUs, and not watts. This means you will need to convert the heater’s wattage into BTUs. To do this, multiply the heater’s maximum wattage by 3.41. (3.41 is how many BTUs are in one watt).

Example: A 1,500-watt heater multiplied by 3.41 BTUs equals 5,115 BTUs/hour. 

Next, you will need to measure the length and width of the room you want to heat up, multiplying the two values together to find the area.

Example: A room 12 ft. long and 12 ft. wide equals 144 sq. ft. 

If the room’s ceiling is higher than the standard 8 feet off the ground, you will also need to increase the square footage value by 12% for each additional foot.

Example: A 9-feet high ceiling means multiplying 144 by 1.12. This equates to 161 sq. ft. 

Finally, a basic rule of thumb is that a house needs anything from 30-60 BTUs per square foot, depending on the climate. Multiply the standard number of BTUs per square foot by the size of the room to determine the total number of BTUs needed for the room.

Example: Let’s say you live in a climate that requires 30 BTUs/sq. ft. Multiply 161 sq. ft. by 30 to get 4,838 BTUs. 

Compare this value to the number of BTUs the heater uses. If the heater’s BTU level is smaller than the room’s required level, you should consider purchasing a space heater with higher wattage. 

5. Are space heaters expensive to use? 

In short, yes. Space heaters can cost the average homeowner more than furnaces since they require more energy to run. But if you use one sparingly and only in a small space, while reducing the central heating temperature, they can be cost effective. 

As of July 2022, the average cost for homeowners in the United States is $0.15 per kilowatt-hour used. For reference, one kilowatt-hour is equivalent to 1,000 watts per hour.

This means that if you use a 1,500-watt space heater for ten hours straight each day, you will be spending $2.25/day. Spread that out to an average 30-day month, and the bill will amount to $67.50.

Written by

Rene has worked 10 years in the HVAC field and now is the Senior Comfort Specialist for PICKHVAC. He holds an HVAC associate degree and EPA & R-410A Certifications. Protection Status