Convert kilowatt-hours to joules

1 kWh=3,600,000J

Use the converter below to change any kilowatt-hours value into joules instantly — with formula, conversion table, and real-world examples.

You have

Equals

3,600,000

Conversion formula

Forward

joules = kilowatt-hours × 3,600,000

Reverse

kilowatt-hours = joules × 2.7778e-7

Example: 10 kWh × 3,600,000 = 36,000,000 J.

About both units

From

Kilowatt-Hour

kWh

The kilowatt-hour equals 3.6 megajoules — energy delivered by 1 kW for 1 hour. It is the standard unit on electricity bills worldwide. A UK home uses about 2900 kWh/year; an EV charge adds 10–80 kWh depending on battery.

Real-world: UK home: ~2900 kWh/year. Tesla Model 3 battery: 60–80 kWh. Typical EV efficiency: 15–20 kWh/100 km.

Read full kilowatt-hour reference →

Joule

The joule is the SI unit of energy, work and heat. Defined as one newton-metre or one watt-second. Named after James Prescott Joule who demonstrated the mechanical equivalent of heat. Lifting a 100 g apple 1 metre requires about 1 J.

Real-world: Lifting a 100 g apple 1 m: ≈ 1 J. 100 kcal snack: 418,400 J. Hand grenade: ~650 kJ.

Read full joule reference →

Kilowatt-Hour to Joule conversion table

Common kilowatt-hours to joules values for quick reference.

Kilowatt-Hour (kWh)	Joule (J)
1 kWh	3,600,000 J
10 kWh	36,000,000 J
100 kWh	360,000,000 J
500 kWh	1,800,000,000 J
1,000 kWh	3,600,000,000 J
5,000 kWh	18,000,000,000 J
10,000 kWh	36,000,000,000 J
50,000 kWh	180,000,000,000 J
100,000 kWh	360,000,000,000 J
500,000 kWh	1,800,000,000,000 J

Tips & common mistakes

Quick tips

1 kWh = 3.6 MJ = 3,600,000 J.
Multiply device power (kW) × time (h) = energy (kWh).
EV "range anxiety" translates to knowing kWh available.

Avoid these

Confusing kWh (energy) with kW (power).
Calculating electric costs by power ignoring duration.
Using "kWh/h" — redundant; it's just kW.

Frequently asked questions

How many joules in a kilowatt-hour?

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

How do I convert kilowatt-hours to joules?

Multiply the kilowatt-hour value by 3,600,000 to get the equivalent in joules.

What is 100 kilowatt-hours in joules?

100 kilowatt-hours equals 360,000,000 joules.

Is a kilowatt-hour bigger than a joule?

Yes. 1 kilowatt-hour equals 3,600,000 joules, so one kilowatt-hour is larger.

How to convert kilowatt-hours to joules without a calculator?

Multiply by 3,600,000 for a quick estimate; use a calculator for precise results.

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