4 Best Smallest Heaters For Heating Small Rooms (Up To 171 Sq Ft)

Big heaters are the worst. These big clunky heaters can take up an abnormal amount of space completely needlessly (let’s not get started on 25+ inch tall ceramic tower heaters). Smaller heaters are, obviously, much smaller and have the same effectiveness (with up to 1500 watt electric input). We check which are the best smallest and yet effective electric heaters on the market (compact design, below $50 price tag).

Namely, small heaters should have 3 key features:

  • Be effective at heating. That means that they should produce enough heat to heat up small and medium-sized rooms (up to 171 sq ft).
  • Be as small as possible (dimensions-wise). No dimension (height, width, depth) should be above 10 inches. On top of that, the complete volume of the heater should be below 500 cubic inches. Some of the most petite heaters can also have below 200 cubic inches of volume.
    dimensions of a mini space heater
    The smallest space heaters can be incredibly small (almost pocket-size). This #2 Teioe mini heater has a total volume of merely 141.5 cubic inches.
  • Be safe. Safety is paramount with space heaters, and even the smallest space heaters are no exception. Getting the safest small heater is ideal.

These kinds of heaters are perfect for small 10×10, 12×12, and even 14×14 rooms.

The problem with most space heaters, however, is that they don’t have thermostats. The thermostat will significantly reduce the running cost of any heater. These mini heaters are quite inexpensive to run but the addition of a thermostat can reduce the running cost even further.

In the list of the best small space heater further on, you will notice that the #1 best small electric heater has a thermostat. That means that it will be able to run at a reduced heating output (and reduced electricity cost) when the thermostat set temperature is met (72°F, for example).

how many square foot do small heaters heat
Thermostat #1 RW Flame mini heater (list below) uses will reduce the heating output to 950W or 2985 BTU or use a fan-only mode to prevent hot or cold spots (non-homogeneous temperature distribution).

Before we check the list of the best small electric heaters for small rooms, let’s first look at the specs that the best smallest heaters should have, namely:

  1. Wattage. This will determine the heating output, expressed in BTUs (British Thermal Units).
  2. Dimensions.
  3. Heating Effectiveness. Dividing wattage input by total volume will give us a metric for how compact any small heater actually is.

How Many Watt Heater To Get For A Small Room?

Electric space heaters are powered by electricity. Due to the use of 110/120V voltage and 15 amp breakers, the upper limit for space heater wattage is 1500 watts.

The smallest space heaters (dimension-wise) will often run on lower wattage (below 1000 watts). However, lower wattage obviously means less heating output.

That’s why the best small heaters should be as small as possible while keeping the wattage (or heating output) high.

Namely, the easiest way to size a small heater for a small room is to follow these 2 rules:

  • You need 30 BTU of heating output per square foot.
  • Every 1 watt of electric input will produce 3.412 BTU of heating output (because electricity is almost 100% converted to heating output).

Example: A 1000-watt heater will produce 3412 BTU of heating output which is enough to adequately heat a 114 sq ft room (this is a 10×10 or 12×12 room, for example).

Here is how many watt small heater you should get to heat up a small room:

Small Heater Wattage (Watts): Heating Room Coverage (Sq Ft):
1500 Watts Up To 171 Sq Ft (14×14 Rooms)
1250 Watts Up To 131 Sq Ft (12×12 Rooms)
1000 Watts Up To 105 Sq Ft (10×10 Rooms)
900 Watts Up To 94 Sq Ft (10×10 Rooms)
800 Watts Up To 84 Sq Ft (8×10 Rooms)
700 Watts Up To 73 Sq Ft (8×10 Rooms)
600 Wats Up To 63 Sq Ft (8×8 Rooms)
500 Watts Up To 53 Sq Ft (Below 8×8 Rooms)
400 Watts Up To 42 Sq Ft (Below 8×8 Rooms)

In most cases, heaters that produce less than 400 watts can hardly be used for adequate heating. You can check these extremely low wattage heaters here.

The idea of the smallest space heaters is that you can still get at least 500 watts of electric input (producing at least 1571 BTU of heating output). The vital part is that these heaters should be as small as possible dimension-wise.

where to place a small electric heater
You can place such small portable heaters pretty much anywhere; in a living room, bedroom, in office, or even to heat up a dormitory room.

Let’s have a look at the dimensions and total volume of the small space heaters:

What Size Should A Small Space Heater Be? (Dimensions, Volume)

The small heater should be small. What does that mean specs-wise?

Well, we can determine which heater is actually small by looking at dimensions as well as looking the total volume of the heater.

Here is the breakdown dimension-by-dimension:

  • Below 10-inch height. Ceramic tower heaters can be up to 30 inches tall; small heaters should have less than 10 inches height. The smallest space heaters can have a height of about 6 inches in total. That’s the pocket-size mini heater.
  • Below 8-inches width. Panel heaters can be very broad (20+ inches in width); mini heaters should have below 8 inches in width.
  • Below 8-inches depth or thickness.

We are talking about space heaters with below 10x8x8 inch dimensions. If you multiply all these dimensions, you get the volume.

Volume is 1 metric that tells us how small any heater is. If you have a 10x10x10 space heater, it has 1000 cubic inches of volume. Most standard 1500 watt heaters do have above 1000 cubic inches of volume.

The smallest ones – including the #1 RWFLAME 1500 watt mini heater with thermostat in the list below – will have below 500 cubic inches of volume.

The tiny mini ones will even have below 200 cubic inches of volume; these heaters, however, are not 1000+ watt heaters. They will have a below 1000 watt electric input and, as a result, produce less than 3412 BTU of heating output.

The best measure of how effective and compact small space heaters are is to divide how many watts of input they have by their total volume (basically, calculating watts per cubic inch):

Heating Effectiveness (Watts Per Cubic Inch)

The easiest way how to tell that you have a compact small heater is just to look at:

  • Wattage.
  • Volume.

The space heaters with the most wattage and least volume are the most compact, right? They will produce a significant amount of heating output while being tiny.

If you calculate this for all space heaters, you can pretty much categorize all heaters into big, standard, and small ones like this:

  • Heating effectiveness less than 1.5 watts per cubic inch = Big clunky heaters.
  • Heating effectiveness of about 2.5 watts per cubic inch = Standard-sizes heaters.
  • Heating effectiveness of more than 3.5 watts per cubic inch = Small compact heaters.

As you will see in the comparison table of the smallest space heaters on the market, 3 out of 4 exceed 4 watts per cubic inch heating effectiveness. In short, these are mini compact heaters, taking a small amount of space but generating ample heating output (enough to heat up small rooms like 10×10, and 12×12 rooms, for example).

Other factors include safety features (such as overheat protection and tip-over protection), quiet operation, and portability.

With all these wattages, heating outputs (BTUs), sizes, and additional factors considered, here are the best small space heaters you can buy right away (they cost less than $50):

Smallest Heaters On The Market

Small Heater: 1. RW FLAME RW3618-B 2. Teioe Mini Heater 3. Coolfor Small Heater 4. Amazon Basic Heater
Photo: smallest 1500 watt electric heater very small desktop electric heater tiny electric heater for small room best mini heater for smallest rooms
Wattage: 1500W / 950W 800W / 400W 600 Watts 500 Watts
Coverage: Up To 171 Sq Ft Up To 91 Sq Ft Up To 68 Sq Ft Up To 57 Sq Ft
Dimensions (W×D×H): 7×5.5×9.2 Inches 5.5×3.1×8.3 Inches 5.6×4.7×5.9 Inches 5.9×3.2×6.0 Inches
Volume: 354.2 Cubic Inches 141.5 Cubic Inches 155.3 Cubic Inches 113.3 Cubic Inches
Watts Per Cubic Inch: 4.23 Watts/Inch3 5.65 Watts/Inch3 3.86 Watts/Inch3 4.41 Watts/Inch3
Weight: 1.59 lbs 1.60 lbs 1.34 lbs 1.43 lbs
Thermostat? energy star no energy star no energy star no
Price: $$$$ $$$$ $$$$ $$$$
Average Rating: 4.9 out of 5 stars 4.5 out of 5 stars 4.5 out of 5 stars 4.1 out of 5 stars
Availability: Check Price Check Price Check Price Check Price

1. Best Small Space Heater With A Thermostat: RW FLAME RW3618-B

Best Small 1500W Electric Heater: R.W.FLAME RW3618-B
Wattage: 1500W / 950W
Coverage: Up To 171 Sq Ft
Dimensions (W×D×H): 7×5.5×9.2 Inches
Volume: 354.2 Cubic Inches
Watts Per Cubic Inch: 4.23 Watts/Inch3
Weight: 1.59 lbs
Thermostat?
Price: $$$$
Rating: 4.9 out of 5 stars

RW Flame is a company specializing in engineering compact heating systems (heaters, fireplaces, panels, and so on). They have tackled the challenge to make a very effective 1500 watt heater WITH a thermostat that is ridiculously small for the heating output. This is the RW FLAME RW3618-B compact mini heater.

While most mini heaters run on less than 1500 watts and don’t have an ECO cost-saving thermostat, the RW FLAME RW3618-B doesn’t run on 1000+ watts, it also has an ECO-friendly thermostat. Specifically, the RW FLAME RW3618-B is a 1500 watt heater that can produce up to 5118 BTU of heating output.

The thermostat will be able to lower the wattage of 950 watts or fan-only function while maintaining the room temperature. Coverage-wise, the RW FLAME RW3618-B is capable of heating up small and medium-sized rooms with up to 171 sq ft area (even 16×16 rooms).

Dimensions-wise, the RW FLAME RW3618-B is 9.2 inches tall, 7 inches wide and it has a 5.5-inch depth. That’s the smallest 1500 watt heater on the market. You can see that the total volume of this mini heater is 354.2 cubic inches; that is about 3 times smaller than a standard 1500 watt heater (they have about 1000 cubic inch volume).

Needless to say, the sheer wattage to cubic inch (heating effectiveness) is 4.23 watts per cubic inch. That’s much above the 2.5 watts per cubic inch average for space heaters. It also weighs less than 2 pounds (1.59 lbs, to be exact).

The con is that there is so much heating being produced in this little heater that the airflow from the heater and thus noise levels are a bit higher. To ensure safety, the RW FLAME RW3618-B has overheat protection as well as tip-over protection.

All in all, the RW FLAME RW3618-B is the smallest 1500 watt heater on the market. It is both very small and most effective, and the only small heater with an ECO-friendly thermostat. It is hands down the best small space heater on the market:

RW FLAME RW3618-B Small Heater Review

Pros
  • One of few 1500 watt heaters that is so incredibly compact and lightweight
  • Has far below 1000 cubic inches volume (354.2 cubic inches, to be exact)
  • Produces up to 5118 BTU of heating output; enough to adequately heat rooms with up to 171 sq ft area (bedrooms, living rooms, etc)
  • Important: It is the only small heater with a thermostat (cost savings)
Cons
  • Due to its compact design, it has to have a high airflow (and thus higher noise levels) to distribute the generated heater
  • Can be out of stock in December, January, and February due to high demand
  • Cannot be run by a small below 1000 watt generator (in event of a power outage)

2. Very Small Portable Electric Heater: Teioe Mini Heater

Very Small Portable Electric Heater: Teioe Mini Heater
Wattage: 800W / 400W
Coverage: Up To 91 Sq Ft
Dimensions (W×D×H): 5.5×3.1×8.3 Inches
Volume: 141.5 Cubic Inches
Watts Per Cubic Inch: 5.65 Watts/Inch3
Weight: 1.60 lbs
Thermostat? energy star no
Price: $$$$
Rating: 4.5 out of 5 stars

As with all things little, small heaters can be cute. And the cutest of them all is the Teioe mini heater. Everybody likes the look of it; what about the specs? If we check under the hood, we can see that this mini heater is not only aesthetic but can also provide a good amount of heating and can heat up a 10×10 room quite easily.

Teioe is a mini heater with dual wattage input; 800 watts (high setting) and 400 watts (low setting). At the high 800W setting, the Teioe mini heater can produce 2730 BTU of heating output. That’s enough to heat up to 91 sq ft all on its own. That’s basically a 10×10 room (or there about).

The dimensions of this cute heater are minuscule. It is only 5.5 inches high, 8.3 inches wide, and it has a 3.1-inch depth. Due to these dimensions, is the perfect small desktop heater. With a total volume of only 141.5 cubic inches, it is also one of the smallest space heaters on the market today.

What is really impressive is its record-breaking 5.65 watts per cubic inch. That’s way above the 2.5 watts per cubic inch average. In short, this small cute heater packs quite a lot of heat for its mini size.

It does, however, not come with a thermostat. You have two settings (Low/High) and you have to switch between them manually. That also means that you will have to continuously run the Teioe at 800W input or 400W input. This will use 0.8 kWh or 0.4 kWh per hour, respectively, costing $0.11 or $0.05 per hour to run (given the average electricity price of $0.1319/kWh).

It does have safety measures like tip-over protection and overheating protection. However, this is a desktop mini heater standing on 4 small feet. The likelihood of tip-over is not insignificant.

With a cost of less than $40, the Teioe mini heater is quite a good and cute small electric heater to choose. It is the most compact and one of the smallest space heaters that everybody will be impressed with:

Teioe Mini Heater Review

Pros
  • Record-high heating effectiveness (5.65 watts per cubic inch)
  • With almost 3000 BTU heating output at 800W setting, it can adequately heat up 10×10 room on its own
  • Perfect as a desktop personal heater
  • Super small dimensions and only 141.5 cubic inches of volume
  • Super cute as well
Cons
  • Doesn’t have a thermostat (can’t reduce the running costs automatically)
  • It can tip-over more easily because it stands on 4 small legs
  • Higher airflow due to how compact it is can increase the noise levels past 40 dB

3. Good Tiny Ceramic Space Heater: Coolfor Small Heater

Good Tiny 600W Heater: Coolfor Small Heater
Wattage: 600 Watts
Coverage: Up To 68 Sq Ft
Dimensions (W×D×H): 5.6×4.7×5.9 Inches
Volume: 155.3 Cubic Inches
Watts Per Cubic Inch: 3.86 Watts/Inch3
Weight: 1.34 lbs
Thermostat? energy star no
Price: $$$$
Rating: 4.5 out of 5 stars

Coolfor is one of the smallest ceramic space heaters. It has a 600 watt electric input and produces a 2047 BTU heating output. That means it can heat (on its own) up to 68 sq ft (that’s an 8×8 room). However, it is most often used as a mini desktop ceramic heater.

It has a shape of a small ball. It is 5.9 inches high, 5.6 inches wide and it has a 4.7-inch depth. That’s basically a 5x5x5 inches small ball-sized heater with a total of 155.3 cubic inches of volume, all in all. In short, it is incredibly small, even for a 600W heater.

If you check the heating effectiveness, it has a considerably above-average 3.86 watts per cubic inch effectiveness. That is quite a lot above average but the #1 RW Flame and #2 Teioe have even higher heating effectiveness; they are even more compact.

It is, however, the lightest space heater weighing only 1.34 lbs.

Obviously, it does not have a thermostat. You have to run it at 600W input all the time, resulting in about $0.08 per hour running cost (given the $0.1319/kWh electricity price).

The advantage small ceramic heaters like Coolfor have is that they heat up really quickly. This quick increase in temperature can present a safety hazard; that’s why Coolfor has tip-over protection and overheating protection. Overheating protection, however, is set to 176°F (the heater will automatically shut off at that temperature) and 176°F is a bit high.

All in all, if you are looking for a small ceramic heater that can provide heating rapidly, the Coolfor is a good choice. It is very tiny, has good stability (for desktop use), it’s pretty cheap (below $30) and it’s the lightest small heater on the market:

Coolfor Small Heater Review

Pros
  • Lightest heater (weighs only 1.34 lbs)
  • Safe stable base, with addition of tip-over protection
  • Ceramic heater provides heating quicker than forced-air heaters
  • Very budget-friendly price
Cons
  • 600 watts might not be enough for adequately heating 10×10 rooms
  • Heating efficiency is high (3.86 watts per cubic inch) but not the highest
  • Abscense of a thermostat
  • Overheat protection is set at a bit too high temperature (176°F)

4. Smallest Electric Heater: Amazon Basic 500W Heater

Smallest Electric Heater: Amazon Basic 500W Heater
Wattage: 500 Watts
Coverage: Up To 57 Sq Ft
Dimensions (W×D×H): 5.9×3.2×6.0 Inches
Volume: 113.3 Cubic Inches
Watts Per Cubic Inch: 4.41 Watts/Inch3
Weight: 1.43 lbs
Thermostat? energy star no
Price: $$$$
Rating: 4.1 out of 5 stars

Amazon Basic products are usually a hit or miss; it all comes down to specs to us. Looking at this small Amazon Basic heater, you can see that the specs are record-low (especially the incredible 113.3 cubic inches of volume). Amazon Basic is thus the smallest electric heater you can buy for as little as $20.

This is a 500 watt low-wattage heater that can generate up to 1706 BTU. If you apply the 30 BTU per sq ft rule of thumb, this tiny heater can be used to heat up to 57 sq ft on its own. It is, however, primarily used as a personal heater; you put it next to you and it heats up the air around you.

The dimensions are just minuscule. Amazon Basic heater is 6 inches high, 5.9 inches wide, and only 3.2 inches thick. You can basically put it in your purse. The total volume is way below 1000 cubic inches most standard heaters have. With 113.3 cubic inches of volume, this is the smallest heater on the market.

It packs quite a lot of heat for its size. The heating effectiveness is 4.41 watts per cubic inch; way above average.

Of course, such a small heater doesn’t have a thermostat and can only run on 1 heating mode (500 watts). It is also not made to last for 10 years or more, of course.

All in all, if you are looking for the cheapest and smallest electric heater, the Amazon Basic mini heater is not a bad choice at all:

Amazon Basic Heater Review

Pros
  • Smallest heater on the market (113.3 cubic inches of volume); it’s literally petite
  • Can be used as a personal space heater
  • High 4.41 watts per cubic inch heating effectiveness
  • Costs about $20; the cheapest small heater on the market
Cons
  • Doesn’t have a thermostat
  • 500 watts does not produce enough heat to heat a small 10×10 room (only personal space)
  • Has only 1 heating mode
  • Not made to last

You now have the benchmark metrics based on which you can determine which heater is the smallest. Looking at the dimensions, wattages, total volume, and calculating heating efficiency (compactness), you can choose the best smallest space heater yourself. To help you out, you can also choose a small heater suggested by the spec-by-spec analysis.

Leave a Comment