BYTETOOLS

Joule to Watt-hour Converter

Convert joules to watt-hours online. 1 J = 0.00027778 Wh. Free, instant Joule-to-Watt-hour converter. Works both ways with a formula and reference table.

Joule → Watt-hour

1 J = 0.00027778 Wh

Joule to Watt-hour conversion table

Joule (J)Watt-hour (Wh)
1 J0.00027778 Wh
2 J0.00055556 Wh
5 J0.00138889 Wh
10 J0.00277778 Wh
25 J0.00694444 Wh
50 J0.01388889 Wh
100 J0.02777778 Wh
  • Instant, live Joule ↔ Watt-hour conversion
  • Accurate to the exact conversion factor
  • Converts in both directions
  • Reference table of common values
  • 100% private — runs entirely in your browser
  • Free, no sign-up, works offline

How to use the Joule to Watt-hour Converter

  1. 1

    Type the number of joules in the first box.

  2. 2

    Read the equivalent value in watt-hours instantly in the second box.

  3. 3

    Or type a Watt-hour value to convert back to joules — it works both ways.

  4. 4

    Copy the result, or check the reference table for common conversions.

About the Joule to Watt-hour Converter

The ByteTools Joule to Watt-hour Converter changes joules into watt-hours instantly. One Joule equals 0.00027778 Watt-hours (Wh), and the tool applies that exact factor as you type so you get a precise answer every time.

Energy conversions appear in nutrition, physics, utility bills and fitness between joules, calories and kilowatt-hours. Everything is calculated locally in your browser — nothing is uploaded — so it is fast, private and works offline. Enter a number in either box to convert both ways, and use the table for common Joule-to-Watt-hour values at a glance.

Frequently asked questions

How many Watt-hours are in a Joule?

One Joule equals 0.00027778 Watt-hours (Wh). To convert, multiply the number of Joules by 0.00027778. For example, 10 Joules = 0.00277778 Watt-hours.

What is the formula to convert Joules to Watt-hours?

Multiply the Joule value by 0.00027778 to get Watt-hours. In symbols, Wh = J × 0.00027778. This converter applies the exact factor automatically so you never round by hand.

How do I convert Watt-hours back to Joules?

Divide by 0.00027778, or multiply by 3600. You can also use our Watt-hour to Joule converter for the reverse direction — it uses the same exact factor.

Is this Joule to Watt-hour converter free and private?

Yes. The conversion runs entirely in your browser with JavaScript — nothing you type is uploaded, logged or stored. It is completely free, needs no sign-up and keeps working offline once loaded.

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