Calories to Watt-hours Converter
1 calorie ≈ 0.00116222222 watt-hours
This is the small calorie. The "Calorie" on food labels is a kilocalorie, which is 1,000 of these.
1 calorie equals 0.00116222 watt-hours
How to convert calories to watt-hours
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.
Wh = cal × 0.001162222222One calorie is 0.001162222222 watt-hours, so a single multiplication converts any value.
0.0116222 Wh ≈ 10 × 0.001162222222This is the small calorie. The "Calorie" on food labels is a kilocalorie, which is 1,000 of these.
Calories to watt-hours conversion table
Common values in calories, converted to watt-hours.
| Calories (cal) | Watt-hours (Wh) |
|---|---|
| 1 | 0.0011622222 |
| 2 | 0.0023244444 |
| 3 | 0.0034866667 |
| 4 | 0.0046488889 |
| 5 | 0.0058111111 |
| 10 | 0.011622222 |
| 20 | 0.023244444 |
| 25 | 0.029055556 |
| 50 | 0.058111111 |
| 100 | 0.11622222 |
| 250 | 0.29055556 |
| 500 | 0.58111111 |
| 1,000 | 1.1622222 |
About these units
caloriecal
The thermochemical calorie: exactly 4.184 joules.
Reference: NIST Special Publication 811.
watt-hourWh
One watt sustained for one hour: exactly 3,600 joules.
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.