---
title: "Energy converter — every unit"
description: "Convert between every energy unit: joule, kilojoule, kilocalorie, watt-hour, kilowatt-hour and more. Tables, exact formulas and a calculator."
url: https://atoneplace.net/convert/energy/
site: "At One Place"
---

# Energy conversions

Every energy unit on the site, and every conversion between them. Each page shows a full table, the exact formula and a live calculator.

## All energy units

*Every energy unit and its size relative to the base unit.*

| Unit | Symbol | In joule |
| --- | --- | --- |
| joule | J | 1 |
| kilojoule | kJ | 1,000 |
| calorie | cal | 4.184 |
| kilocalorie | kcal | 4,184 |
| watt-hour | Wh | 3,600 |
| kilowatt-hour | kWh | 3,600,000 |
| British thermal unit | BTU | 1,055.055853 |
| electronvolt | eV | 1.602176634 × 10^-19 |

## Common conversions

- [Joules to Kilojoules](https://atoneplace.net/convert/joules-to-kilojoules/)
- [Joules to Kilocalories](https://atoneplace.net/convert/joules-to-kcal/)
- [Joules to Watt-hours](https://atoneplace.net/convert/joules-to-watt-hours/)
- [Joules to Kilowatt-hours](https://atoneplace.net/convert/joules-to-kwh/)
- [Joules to British thermal units](https://atoneplace.net/convert/joules-to-btu/)
- [Kilojoules to Joules](https://atoneplace.net/convert/kilojoules-to-joules/)
- [Kilojoules to Kilocalories](https://atoneplace.net/convert/kilojoules-to-kcal/)
- [Kilojoules to Watt-hours](https://atoneplace.net/convert/kilojoules-to-watt-hours/)
- [Kilojoules to Kilowatt-hours](https://atoneplace.net/convert/kilojoules-to-kwh/)
- [Kilojoules to British thermal units](https://atoneplace.net/convert/kilojoules-to-btu/)
- [Kilocalories to Joules](https://atoneplace.net/convert/kcal-to-joules/)
- [Kilocalories to Kilojoules](https://atoneplace.net/convert/kcal-to-kilojoules/)
- [Kilocalories to Watt-hours](https://atoneplace.net/convert/kcal-to-watt-hours/)
- [Kilocalories to Kilowatt-hours](https://atoneplace.net/convert/kcal-to-kwh/)
- [Kilocalories to British thermal units](https://atoneplace.net/convert/kcal-to-btu/)
- [Watt-hours to Joules](https://atoneplace.net/convert/watt-hours-to-joules/)
- [Watt-hours to Kilojoules](https://atoneplace.net/convert/watt-hours-to-kilojoules/)
- [Watt-hours to Kilocalories](https://atoneplace.net/convert/watt-hours-to-kcal/)
- [Watt-hours to Kilowatt-hours](https://atoneplace.net/convert/watt-hours-to-kwh/)
- [Watt-hours to British thermal units](https://atoneplace.net/convert/watt-hours-to-btu/)
- [Kilowatt-hours to Joules](https://atoneplace.net/convert/kwh-to-joules/)
- [Kilowatt-hours to Kilojoules](https://atoneplace.net/convert/kwh-to-kilojoules/)
- [Kilowatt-hours to Kilocalories](https://atoneplace.net/convert/kwh-to-kcal/)
- [Kilowatt-hours to Watt-hours](https://atoneplace.net/convert/kwh-to-watt-hours/)
- [Kilowatt-hours to British thermal units](https://atoneplace.net/convert/kwh-to-btu/)
- [British thermal units to Joules](https://atoneplace.net/convert/btu-to-joules/)
- [British thermal units to Kilojoules](https://atoneplace.net/convert/btu-to-kilojoules/)
- [British thermal units to Kilocalories](https://atoneplace.net/convert/btu-to-kcal/)
- [British thermal units to Watt-hours](https://atoneplace.net/convert/btu-to-watt-hours/)
- [British thermal units to Kilowatt-hours](https://atoneplace.net/convert/btu-to-kwh/)

## Sources

- Guide for the Use of the International System of Units (SP 811) — NIST (https://www.nist.gov/pml/special-publication-811) [Public domain (US Government)]
- The International System of Units (SI Brochure) — Bureau International des Poids et Mesures (https://www.bipm.org/en/publications/si-brochure)