Wh to kWh Converter
Convert watt-hours to kilowatt-hours — divide by one thousand. Results update as you type; exact factors shown.
One watt-hour is 0.001 kilowatt-hours — see the exact factor, not a rounded rule of thumb.
How the wh to kwh converter works
Energy converts through the joule. A thermochemical calorie is exactly 4.184 J, so a food Calorie (kcal) is 4.184 kJ. A kilowatt-hour is exactly 3.6 MJ. A BTU is 1,055.056 J and a US therm is 100,000 BTU.
The UK is metric for most trade and science but keeps miles, pints, stone and mpg (with the imperial gallon) in daily life.
Common energy conversions
| From | To | Units |
|---|---|---|
| 100 Wh | 0.1 kWh | watt-hours to kilowatt-hours |
| 250 Wh | 0.25 kWh | watt-hours to kilowatt-hours |
| 500 Wh | 0.5 kWh | watt-hours to kilowatt-hours |
| 750 Wh | 0.75 kWh | watt-hours to kilowatt-hours |
| 1,000 Wh | 1 kWh | watt-hours to kilowatt-hours |
| 1,500 Wh | 1.5 kWh | watt-hours to kilowatt-hours |
| 2,000 Wh | 2 kWh | watt-hours to kilowatt-hours |
| 5,000 Wh | 5 kWh | watt-hours to kilowatt-hours |
| 10,000 Wh | 10 kWh | watt-hours to kilowatt-hours |
| 13,500 Wh | 13.5 kWh | watt-hours to kilowatt-hours |
| 50,000 Wh | 50 kWh | watt-hours to kilowatt-hours |
| 100,000 Wh | 100 kWh | watt-hours to kilowatt-hours |
Units in this converter and their exact factors
| Unit | Symbol | One unit in joules |
|---|---|---|
| joule | J | 1 joule |
| kilojoule | kJ | 1,000 joule |
| megajoule | MJ | 1,000,000 joule |
| calorie (thermochemical) | cal | 4.184 joule |
| kilocalorie (food Calorie) | kcal | 4,184 joule |
| watt-hour | Wh | 3,600 joule |
| kilowatt-hour | kWh | 3,600,000 joule |
| British thermal unit | BTU | 1,055.05585262 joule |
| therm (US) | thm | 105,505,585.262 joule |
| foot-pound | ft·lb | 1.3558179483 joule |
FAQFrequently asked questions about energy conversion
How many Wh in a kWh?
Exactly 1,000.
What is a 13,500 Wh battery in kWh?
13.5 kWh — a Tesla Powerwall.
Why are phone batteries in mAh instead?
Because milliamp-hours only become energy once multiplied by the voltage. A 5,000 mAh phone battery at 3.85 V is about 19 Wh.
What does a fridge use?
Roughly 1 to 2 kWh a day, which is 1,000 to 2,000 Wh.
How do I convert Wh to kWh?
Move the decimal point three places left.
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Physical Laboratory (NPL) — United Kingdom's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.