Convert Watt-hours to Calories
Convert Watt-hours to Calories instantly. 1 Watt-hour (Wh) equals 860.4207 Calories (cal).
Watt-hours to Calories conversion table
| Watt-hours (Wh) | Calories (cal) |
|---|---|
| 1 Wh | 860.4207 cal |
| 2 Wh | 1,720.84 cal |
| 3 Wh | 2,581.26 cal |
| 5 Wh | 4,302.1 cal |
| 10 Wh | 8,604.21 cal |
| 20 Wh | 17,208.41 cal |
| 50 Wh | 43,021.03 cal |
| 100 Wh | 86,042.07 cal |
| 500 Wh | 430,210.33 cal |
| 1,000 Wh | 860,420.65 cal |
1 Watt-hour = 860.4207 Calories · multiply Watt-hours by 860.4207
About converting Watt-hours to Calories
Watt-hours (Wh) and Calories (cal) are both units of energy, so converting between them is a single multiplication: multiply your Watt-hours figure by 860.4207. Ten Watt-hours comes to 8,604.21 Calories, and a hundred works out at 86,042.07 Calories.
Rule of thumb: going from Watt-hours to Calories multiplies, so the figure always grows — one Watt-hour is already 860.4207 Calories. If your answer came out smaller, you have the conversion the wrong way round.
What is a Watt-hour?
A watt-hour is energy, not power, and that distinction trips people up constantly. A watt is a rate — energy per second — so a watt-hour is what you get by sustaining that rate for an hour: a quantity of energy expressed as "this much power for this long". It is the natural unit for anything that stores energy and releases it gradually, which is why phone and laptop batteries are rated in watt-hours rather than the milliamp-hours stamped on the cell, and why airlines police lithium batteries by their watt-hour rating. Capacity in watt-hours tells you how long a load can run; watts alone never can.
What is a Calory?
The calorie is the unit most likely to be misread, because there are two of them. The small calorie — the one this converter uses — is approximately the heat needed to warm a gram of water by one degree Celsius, and it is a tiny amount of energy. The "calories" printed on food labels are not these: a food Calorie, traditionally written with a capital C, is a thousand small calories, properly a kilocalorie. So a 2,000-calorie daily diet is really about 8.4 million small calories. Several slightly different calories were defined historically; the thermochemical calorie used here is fixed at exactly 4.184 joules.
To put both in perspective: a phone battery holds somewhere around 15 watt-hours, while an apple holds roughly 95,000 small calories.
The converter above updates as you type, and the table lists common values for quick reference. Need the opposite direction? Use the Calories to Watt-hours converter, or browse all Energy converters.
Frequently asked questions
How many Calories are in one Watt-hour?
There are 860.4207 Calories in one Watt-hour.
How do I convert Watt-hours to Calories?
Multiply the number of Watt-hours by 860.4207. For example, 10 Watt-hours = 8,604.21 Calories.
What is 100 Watt-hours in Calories?
100 Watt-hours is equal to 86,042.07 Calories.
How do I convert Calories to Watt-hours?
Multiply the Calories value by 0.001162 (or divide by 860.4207).
Is this Watt-hours to Calories conversion exact?
The definition is exact — Watt-hours and Calories are both fixed against the same base by international agreement — but the decimal shown here is rounded for readability, because the true ratio does not terminate. For engineering or scientific work, carry more decimal places than this page displays.
What is a Watt-hour?
A watt-hour is energy, not power, and that distinction trips people up constantly. A watt is a rate — energy per second — so a watt-hour is what you get by sustaining that rate for an hour: a quantity of energy expressed as "this much power for this long". It is the natural unit for anything that stores energy and releases it gradually, which is why phone and laptop batteries are rated in watt-hours rather than the milliamp-hours stamped on the cell, and why airlines police lithium batteries by their watt-hour rating. Capacity in watt-hours tells you how long a load can run; watts alone never can.
What is a Calory?
The calorie is the unit most likely to be misread, because there are two of them. The small calorie — the one this converter uses — is approximately the heat needed to warm a gram of water by one degree Celsius, and it is a tiny amount of energy. The "calories" printed on food labels are not these: a food Calorie, traditionally written with a capital C, is a thousand small calories, properly a kilocalorie. So a 2,000-calorie daily diet is really about 8.4 million small calories. Several slightly different calories were defined historically; the thermochemical calorie used here is fixed at exactly 4.184 joules.