Energy Converter

Convert energy units including joules, kilojoules, calories, kilocalories, BTU, watt-hours, kilowatt-hours, foot-pounds, electronvolts, and more.

Convert Energy

1 joule = 0.000277778 watt-hour
Your converted energy result will appear here.

Common energy conversions

Joules to watt-hours:
1 J = 0.000277778 Wh

Watt-hours to joules:
1 Wh = 3,600 J

Kilowatt-hours to joules:
1 kWh = 3,600,000 J

BTU to joules:
1 BTU = 1055.05585 J

Where energy conversions are used

Energy conversions are useful for electrical usage, batteries, heating and cooling, physics, engine output, food energy, thermal systems, and mechanical work.

Use this converter when comparing mechanical, electrical, thermal, and scientific energy units.

What your energy result means

Your result shows the entered energy converted from the starting unit into the selected ending unit. The calculator also shows the conversion rate used so you can verify the calculation.

For engineering, electrical, or thermal work, make sure the energy unit matches the formulas, equipment ratings, or usage data you are working with.

Energy converter tips

Frequently asked questions

What is energy?

Energy is the capacity to do work, produce heat, or cause change in a system.

What is the SI unit of energy?

The SI unit of energy is the joule, abbreviated as J.

How many joules are in a kilowatt-hour?

One kilowatt-hour equals 3,600,000 joules.

What is BTU used for?

BTU is commonly used for heat energy, heating systems, cooling systems, and HVAC equipment comparisons.

Can I convert negative energy values?

This converter is designed for energy magnitude conversions, so it uses non-negative values.