Kilocalories to Watt Hours
Type a value in either box to convert between kilocalories and watt hours. The factor is 1.16222.
| Kilocalories | Watt Hours |
|---|---|
| 1 kcal | 1.162222 Wh |
| 2 kcal | 2.324444 Wh |
| 3 kcal | 3.486667 Wh |
| 5 kcal | 5.811111 Wh |
| 10 kcal | 11.622222 Wh |
| 25 kcal | 29.055556 Wh |
| 50 kcal | 58.111111 Wh |
| 100 kcal | 116.222222 Wh |
How to use
- Enter a value in the Kilocalories field.
- The Watt Hours figure appears immediately — no button to press.
- Typing in the Watt Hours field converts back to Kilocalories the same way.
- Use the reference table for the values that come up most often.
Kilocalories to Watt Hours formula
To convert kilocalories to watt hours, multiply by 1.16222222.
Wh = kcal × 1.16222222
Put another way, one kilocalorie is exactly 523/450 watt hours.
Why this factor: the kilocalorie and the watt-hour are both defined against the joule, so dividing one definition by the other gives 1.16222222 directly. Both definitions are set out in full below.
To go the other way, divide by 1.16222222 — or use the Watt Hours to Kilocalories converter, which is the same calculation reversed.
Worked example
Start with 100 kcal. Multiply by 1.16222222 to get 116.222222 Wh.
100 kcal × 1.16222222 = 116.222222 Wh
The converter above does this for any value you type, in either direction.
What is a kilocalorie?
A kilocalorie is 1,000 calories, and is what food labeling calls a 'Calorie'.
Definition: Exactly 4,184 joules.
Where it is used: Nutrition and dietary energy in the US and much of the world, and metabolic measurements.
Worth knowing: Written with a capital C ('Calorie') or as 'kcal' on labels. This is the unit meant by everyday talk about counting calories.
What is a watt-hour?
A watt-hour is the energy delivered by one watt of power sustained for one hour.
Definition: Exactly 3,600 joules.
Where it is used: Battery capacity for laptops, e-bikes and power tools, and small-scale energy metering.
Worth knowing: Airline lithium-battery limits are set in watt-hours, which is why laptop and power-bank capacities are labelled in Wh.
Kilocalories vs Watt Hours
The kilocalorie and the watt-hour belong to the same family of units, so converting between them is usually a matter of shifting a decimal point or applying a small whole-number factor.
Frequently asked questions
How many watt hours are in a kilocalorie?
One kilocalorie equals 1.16222222 watt hours.
What is the formula to convert kilocalories to watt hours?
Multiply the number of kilocalories by 1.16222222. To reverse it, divide by 1.16222222 instead.
How do I convert watt hours back to kilocalories?
Divide by 1.16222222, which is the same as multiplying by 0.86042065.
How many watt hours are in 10 kilocalories?
10 kcal works out to 11.622222 Wh.
Is there anything to watch out for with kilocalories?
Written with a capital C ('Calorie') or as 'kcal' on labels. This is the unit meant by everyday talk about counting calories.
How is the kilocalorie defined?
Exactly 4,184 joules.