Watt-hours to British Thermal Units Converter
1 watt-hour ≈ 3.41214163 British thermal units
Several BTU definitions exist. This converter uses the International Table BTU, the one used by HVAC equipment ratings.
1 watt-hour equals 3.41214 British thermal units
How to convert watt-hours to British thermal units
Calories here are thermochemical (4.184 J), while BTU uses the International Table definition. A kilowatt-hour is energy (3.6 MJ), not power; a food Calorie is a kilocalorie.
BTU = Wh × 3.412141633One watt-hour is 3.412141633 British thermal units, so a single multiplication converts any value.
34.1214 BTU ≈ 10 × 3.412141633Several BTU definitions exist. This converter uses the International Table BTU, the one used by HVAC equipment ratings.
Watt-hours to British thermal units conversion table
Common values in watt-hours, converted to British thermal units.
| Watt-hours (Wh) | British thermal units (BTU) |
|---|---|
| 1 | 3.4121416 |
| 2 | 6.8242833 |
| 3 | 10.236425 |
| 4 | 13.648567 |
| 5 | 17.060708 |
| 10 | 34.121416 |
| 20 | 68.242833 |
| 25 | 85.303541 |
| 50 | 170.60708 |
| 100 | 341.21416 |
| 250 | 853.03541 |
| 500 | 1,706.0708 |
| 1,000 | 3,412.1416 |
About these units
watt-hourWh
One watt sustained for one hour: exactly 3,600 joules.
British thermal unitBTU
The International Table BTU: 1,055.05585262 joules. The US heating and cooling unit.
Reference: NIST Special Publication 811.
Sources and precision
Table results are rounded to 8 significant digits; formula constants may be rounded to 10. Worked example answers use 6 significant digits. The converter starts at 6 significant digits and lets you change display precision. Calculations use the stored factors without intermediate rounding. Exact unit definitions do not make an input measurement more precise; conventional and measured factors follow the assumptions stated here.