Watt-hour to Kilowatt-hour (Wh to kWh)
Result
0.001 Kilowatt-hour
Formula
kWh = Wh × 0.001
1 Wh = 0.001 kWh, and 1 kWh = 1,000 Wh.
The joule is the SI unit of energy. The calorie used here is the thermochemical calorie, exactly 4.184 J; a kilowatt-hour is exactly 3.6 MJ; the BTU is the International Table BTU (1,055.05585262 J).
Worked examples
- 1 Wh × 0.001 = 0.001 kWh
- 10 Wh × 0.001 = 0.01 kWh
- 100 Wh × 0.001 = 0.1 kWh
Common mistakes
- Food "Calories" (capital C) are kilocalories: a 250 Calorie snack contains 250 kcal, or 1,046 kJ.
- kW is power and kWh is energy: a 2 kW heater running for 3 hours uses 6 kWh.
- The International Table calorie (4.1868 J) is slightly larger than the thermochemical calorie (4.184 J); engineering steam tables use the former.
Watt-hour to Kilowatt-hour table
| Watt-hour (Wh) | Kilowatt-hour (kWh) |
|---|---|
| 1 | 0.001 |
| 2 | 0.002 |
| 5 | 0.005 |
| 10 | 0.01 |
| 20 | 0.02 |
| 50 | 0.05 |
| 100 | 0.1 |
| 1,000 | 1 |
The units
- Watt-hour (Wh)
- 1 Watt-hour = 3,600 Joule.
- Kilowatt-hour (kWh)
- 1 Kilowatt-hour = 3,600,000 Joule.
Sources for these factors
- Guide for the Use of the International System of Units (SP 811), Appendix B: conversion factors — NIST
- The International System of Units (SI Brochure), 9th edition — BIPM
Last reviewed against these sources. An automated check recomputes every factor from its definition on each build. How we check accuracy