How to Convert Watt-hours to British thermal units (Wh to BTU)
Energy conversions link food labels in kJ and kcal, SP Group bills in kWh and air-conditioner capacity in BTU. This guide shows how to convert watt-hours into british thermal units by hand, with examples and a quick-reference table.
The conversion
To convert watt-hours to british thermal units, multiply the value by 3.4121416416. To go the other way, divide by the same number (or multiply by 0.2930710694). For a quick estimate, multiply by about 3.4.
British thermal units = watt-hours × 3.4121416416
Worked examples
- 3 Wh = 10.2364 BTU
- 12.5 Wh = 42.6518 BTU
- 75 Wh = 255.9106 BTU
Watt-hours to British thermal units table
| Watt-hours | British thermal units |
|---|---|
| 1 Wh | 3.4121 BTU |
| 2 Wh | 6.8243 BTU |
| 5 Wh | 17.0607 BTU |
| 10 Wh | 34.1214 BTU |
| 20 Wh | 68.2428 BTU |
| 25 Wh | 85.3035 BTU |
| 50 Wh | 170.6071 BTU |
| 100 Wh | 341.2142 BTU |
| 250 Wh | 853.0354 BTU |
| 500 Wh | 1,706.07 BTU |
| 1,000 Wh | 3,412.14 BTU |
Common questions
Is Wh to BTU exact?
The factors used here are the internationally defined values where they exist; results are rounded for display only.
How do I convert back?
Use the British thermal units to Watt-hours converter.
Mistakes to avoid
Rounding the factor too early
Using 3 instead of 3.28 for feet per metre introduces an error of almost 9% before you have started.
Multiplying when you should divide
Converting to a smaller unit gives a bigger number, and converting to a larger unit gives a smaller one. If your answer moves the wrong way, you have inverted the factor.
Mixing similar-sounding units
US and imperial gallons, pints and tons are different sizes, and decimal kilobytes differ from binary kibibytes.
Background
Singapore adopted the metric system in the 1970s, replacing imperial units and traditional Chinese measures in most official uses. Metric units are now standard in schools, trade and government, but older units survive in property, markets and imported goods.
Unit conversion is simply multiplication by a fixed ratio. The ratio between two units of the same quantity never changes, so once you know it you can convert any value in either direction.
A conversion table is handy for common values, but a calculator is faster and avoids interpolation errors for anything in between.
For any value, use the Watt-hours to British thermal units Converter or browse all energy converters.
Run your own numbers: Watt-hours to British thermal units Converter