Marks Calc

watt-hours to joules

Convert watt-hour to joule — instant, free, with the formula shown.

1 Wh=3600 J

How to convert watt-hour to joule

To convert watt-hour to joule, multiply by 3600:

J = Wh × 3600

For example, 10 Wh × 3600 = 36000 J.

Wh to J conversion table

watt-hours (Wh)joules (J)
1 Wh3600 J
2 Wh7200 J
5 Wh18000 J
10 Wh36000 J
25 Wh90000 J
50 Wh180000 J
100 Wh360000 J
250 Wh900000 J
500 Wh1800000 J
1000 Wh3600000 J
Reverse: Joule to Watt-hour

Other watt-hour conversions

Convert to joule from another unit

Wh to J — frequently asked

How many joules are in 1 watt-hour?

1 watt-hour = 3600 joules (Wh × 3600 = J).

What is the formula to convert watt-hour to joule?

Multiply your watt-hour value by 3600 to get joule.

How do I convert 10 watt-hours to joules?

10 Wh = 36000 J. For 100 Wh the answer is 360000 J. Use the calculator on this page for any other value.

When to convert watt-hour to joule

1Electricity bills (kWh)
2Nutrition labels (kcal / food cal)
3HVAC and heating (BTU, therms)
4Physics and chemistry (J, eV)

Energy conversion — common questions

Is a food calorie the same as a calorie?

No — a food 'Calorie' (capital C) actually means 1 kilocalorie = 1,000 small calories = 4,184 J. Nutrition labels typically write 'cal' meaning kcal.

How many joules in 1 kWh?

1 kWh = 3,600,000 J (3.6 MJ). Because 1 kW × 1 hour = 1,000 W × 3,600 s = 3,600,000 J.

What is a BTU?

British Thermal Unit — the energy required to raise 1 pound of water by 1 °F. 1 BTU ≈ 1,055 J.

See all energy converters