Milliwatt is 0.001 watt units.
Milliwatts to BTU per hour Converter — mW to BTU/h
Convert Milliwatt (mW) to BTU per hour (BTU/h) using the exact conversion factor (1 milliwatt = 0.0034121416 btu per hour). See the formula, worked examples, and conversion table.
Milliwatts to BTU per hour converter
Converter
Engineering Converter
Convert common stress, force, torque, power, and energy units used in engineering.
Context values
Some unit families need one extra value for a physically accurate result.
Power rate using BTU per hour.
Result = input x 0.001 / 0.2930710702.
Power units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Milliwatts to BTU per hour
Milliwatt and BTU per hour both measure a quantity used in structural or mechanical engineering — commonly stress, pressure, force, torque, power, or energy — where converting between the unit conventions used in different regions, industries, or equipment specifications is a routine part of design work. Specifically: Milliwatt is 0.001 watt units, and power rate using BTU per hour.
Formula
btu per hour = milliwatts × 0.00341214163313
This factor comes from each unit's defined relationship to the category's base unit: 1 milliwatt equals 0.001 base units, and 1 btu per hour equals 0.293071070172 base units, so dividing one by the other gives the direct milliwatt-to-btu per hour factor of 0.00341214163313.
Simple example
1 mW × 0.003412141633 = 0.0034121416 BTU/h
1 milliwatt = 0.0034121416 btu per hour.
Real-world example
100 mW × 0.003412141633 = 0.3412141633 BTU/h
100 milliwatts = 0.3412141633 btu per hour.
Conversion table
| Milliwatt (mW) | BTU per hour (BTU/h) |
|---|---|
| 1 mW | 0.0034121416 BTU/h |
| 10 mW | 0.0341214163 BTU/h |
| 50 mW | 0.1706070817 BTU/h |
| 100 mW | 0.3412141633 BTU/h |
| 500 mW | 1.706070817 BTU/h |
| 1,000 mW | 3.412141633 BTU/h |
Reverse conversion: BTU per hour to Milliwatt
0.0034121416 BTU/h × 293.0710702 = 0.9999999903 mW
0.0034121416 btu per hour = 0.9999999903 milliwatts.
milliwatts = btu per hour × 293.071070172
For a page dedicated to this direction, see BTU per hour to Milliwatt.
Understanding the Milliwatt (mW)
Milliwatt is 0.001 watt units.
Understanding the BTU per hour (BTU/h)
Power rate using BTU per hour.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many btu per hour are in 1 milliwatt?
1 milliwatt equals 0.0034121416 btu per hour, using the exact defined conversion factor rather than an estimate.
How do I convert milliwatt to btu per hour?
Multiply the milliwatt value by 0.003412141633. The converter above does this instantly to whatever precision you set.
How do I convert btu per hour back to milliwatt?
Use the reverse factor: 1 btu per hour equals 293.0710702 milliwatts. You can also use the swap control in the converter above to flip the direction instantly.
What is a milliwatt?
Milliwatt (mW) is a unit of engineering.
What is a btu per hour?
BTU per hour (BTU/h) is a unit of engineering.
Is the milliwatt to btu per hour conversion exact?
Yes. Both milliwatt and btu per hour are defined by fixed standards rather than physical artifacts, so the factor of 0.003412141633 used above is exact to as many digits as you choose to display.
Why do engineering unit conventions vary so much by region and industry?
Pressure, force, and stress can be expressed in metric (pascal, newton), US customary (psi, pound-force), or older and industry-specific units (atmosphere, torr, kip) depending on the country, industry, and even the equipment manufacturer, which is why engineers routinely need to convert between them when working across specs from different sources.