Watts to Joules
Energy converter

Joules to Watt-hours Converter

Convert energy from joules to watt-hours for batteries and electronics.

  • Joules (J)
  • Kilojoules (kJ)

How Joules to Wh works

Watt-hours (Wh) are commonly used to measure the capacity of small batteries like those in laptops and phones.

Since 1 Watt is 1 Joule per second, and an hour has 3,600 seconds, 1 Watt-hour equals exactly 3,600 Joules.

Formula
1Wh = J ÷ 3,600

Divide joules by 3,600 to get watt-hours.

Joules to Wh conversion table

Reference Table4 rows
Common joule values converted to watt-hours.
Joules↕Watt-hours (Wh)↕
3,600 J
1 Wh
18,000 J
5 Wh
36,000 J
10 Wh
180,000 J
50 Wh
💡 Click any row to auto-fill the calculator aboveClick column headers to sort

FAQ: Joules to Wh

How many joules are in a watt-hour?

One watt-hour is exactly 3,600 joules.

Tools related to Joules to Wh

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