heater grate

Heat BTU Calculator

British Thermal Units (BTUs) are a measurement of energy required to increase temperature, frequently used when discussing heaters. BTUs are defined as the amount of energy required to raise the temperature of one pound of water by one degree Fahrenheit. Now, heater manufacturers use BTUs to make it easier to compare heaters with different capacities and designs. In general, the larger the number of BTUs, the higher the capacity of the heater. For example, a 1,000-BTU heater will use more energy than a 200-BTU. Use the following calculator to understand how many BTUs are needed to heat your indoor space.

Learn more about BTUs and other HVAC terms in our HVAC Glossary.

Heating BTUs

Enter information about your space to calculate the amount of British Thermal Units (BTUs) required to properly heat it.

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Your area requires {{ calcFinal }} BTUs to heat properly.

If you live in North America, use the map below to choose the appropriate climate zone number.

climate zone map of North America

Generally, the higher the BTUs, the more powerful the heater. However, if you’re searching for optimal heating, you’ll also want to consider airflow, air quality, and overall power usage. The BTU output of a heater is usually listed on a product’s packaging, so you’ll be able to find and compare numbers easily.

The Importance of Measuring Heating Energy Usage

Heating your home efficiently might seem like a big expense, but it doesn’t have to be. By understanding how much energy your heater uses and how to measure your heater’s energy usage, you can make sure that you’re using the right amount of energy to keep your home comfortable.

Measuring your heating energy usage can also help you find ways to reduce your energy usage and save money on your heating bill. For example, if you notice that your heater is using more energy than usual, you may be able to adjust your thermostat to reduce your energy usage. Or, if you find that your home is too cold in the winter, you may be able to add insulation to your home to reduce your energy usage.

Heating your home efficiently is important for both your wallet and the environment. By understanding your heater’s energy usage, you can make sure that you’re using the right amount of energy to keep your home comfortable and save money on your heating bill.


Still have questions? Ask an HVAC expert directly via chat or phone.



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