A watt-hour is 3,600 joules.
Watt-hours to Kilocalories Converter — Wh to kcal
Convert Watt-hour (Wh) to Kilocalorie (kcal) using the exact conversion factor (1 watt-hour = 0.8604206501 kilocalorie). See the formula, worked examples, conversion table, and common uses.
Watt-hours to Kilocalories converter
Converter
Energy Converter
Convert joules, calories, kilowatt-hours, BTU, electronvolts, therms, and mechanical work units.
Context values
Some unit families need one extra value for a physically accurate result.
A kilocalorie is 1,000 calories.
Result = input x 3600 / 4184.
Energy uses the joule as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Watt-hours to Kilocalories
Watt-hour and Kilocalorie both measure energy, and the conversion is especially useful for comparing nutrition labels (kilocalories) against scientific energy figures (joules). Watt-hour is most often used for phone, laptop, and power-bank battery capacity ratings.
Formula
kilocalories = watt-hours × 0.860420650096
This factor comes from each unit's defined relationship to the category's base unit: 1 watt-hour equals 3600 base units, and 1 kilocalorie equals 4184 base units, so dividing one by the other gives the direct watt-hour-to-kilocalorie factor of 0.860420650096.
Simple example
1 Wh × 0.8604206501 = 0.8604206501 kcal
1 watt-hour = 0.8604206501 kilocalories.
Real-world example
100 Wh × 0.8604206501 = 86.04206501 kcal
100 watt-hours = 86.04206501 kilocalories.
Conversion table
| Watt-hour (Wh) | Kilocalorie (kcal) |
|---|---|
| 1 Wh | 0.8604206501 kcal |
| 10 Wh | 8.604206501 kcal |
| 100 Wh | 86.04206501 kcal |
| 500 Wh | 430.210325 kcal |
| 1,000 Wh | 860.4206501 kcal |
| 2,000 Wh | 1,720.8413 kcal |
Reverse conversion: Kilocalorie to Watt-hour
0.8604206501 kcal × 1.162222222 = 1 Wh
0.8604206501 kilocalories = 1 watt-hours.
watt-hours = kilocalories × 1.16222222222
For a page dedicated to this direction, see Kilocalorie to Watt-hour.
Understanding the Watt-hour
Watt-hour (Wh) measures energy. The energy delivered by one watt of power sustained for one hour — equal to 3,600 joules. It is classified as a metric derived energy unit.
Where it's used: Universal — standard consumer-electronics and battery energy unit worldwide
Wh vs. kWh. The same unit at different scales: 1,000 Wh equals 1 kWh. Wh suits small consumer-electronics batteries; kWh is used for household electricity billing and larger energy storage.
Uses of the Watt-hour today
- Phone, laptop, and power-bank battery capacity ratings
- Electric-vehicle battery capacity specifications
- Small-scale renewable energy (solar panel) output ratings
Understanding the Kilocalorie (kcal)
A kilocalorie is 1,000 calories.
Watt-hour — sources
- BIPM SI Brochure — Watt-hour as a common energy unit derived from the coherent SI units watt and second (via the hour).
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many kilocalories are in 1 watt-hour?
1 watt-hour equals 0.8604206501 kilocalories, using the exact defined conversion factor rather than an estimate.
How do I convert watt-hour to kilocalorie?
Multiply the watt-hour value by 0.8604206501. The converter above does this instantly to whatever precision you set.
How do I convert kilocalorie back to watt-hour?
Use the reverse factor: 1 kilocalorie equals 1.162222222 watt-hours. You can also use the swap control in the converter above to flip the direction instantly.
What is a watt-hour?
Watt-hour (Wh) measures energy. The energy delivered by one watt of power sustained for one hour — equal to 3,600 joules. It is classified as a metric derived energy unit.
What is a kilocalorie?
Kilocalorie (kcal) is a unit of energy.
Is the watt-hour to kilocalorie conversion exact?
Yes. Both watt-hour and kilocalorie are defined by fixed standards rather than physical artifacts, so the factor of 0.8604206501 used above is exact to as many digits as you choose to display.
What is the difference between wh vs. kwh?
The same unit at different scales: 1,000 Wh equals 1 kWh. Wh suits small consumer-electronics batteries; kWh is used for household electricity billing and larger energy storage.
Where is the watt-hour still used today?
Universal — standard consumer-electronics and battery energy unit worldwide