Power converter

Joules to Watts Calculator

Find power in watts from total energy in joules and time.

How Joules to Watts works

Since a watt is defined as one joule per second, you can find the power of a device if you know the total energy it consumed and the time it was running.

Simply divide the joules by the time in seconds.

Formula

1W = J ÷ s

Divide total joules by total seconds.

Joules to Watts conversion table

Reference Table4 rows

Joules to watts over 1 hour (3,600s).
Energy (Joules)↕	Power (Watts)↕
3,600 J	1 W
36,000 J	10 W
360,000 J	100 W
3,600,000 J	1,000 W (1 kW)

💡 Click any row to auto-fill the calculator aboveClick column headers to sort

FAQ: Joules to Watts

How do you convert joules to watts?

Divide energy in joules by the time in seconds. For example, 3600 J over 3600 seconds is 1 Watt.

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