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Convert Kilowatt-hours to Calories

1 kilowatt-hour is 860,420.650096 cal. One kilowatt-hour is exactly 860420.650096 calories.

One kilowatt-hour is 860420.65 calories. To convert kilowatt-hours to calories, multiply by 860420.65; to go the other way, divide by 860420.65 or multiply by 1.1622 × 10^-6. The factor is exact rather than rounded: it follows from NIST Special Publication 811. A thousand watt-hours, and the unit every electricity bill is added up in.

Factor checked against the defining standard · How we check

Calories
860,420.650096 cal
Kilowatt-hours × 860420.65
value * 860420.650096860,420.65 cal

1 kilowatt-hour in every energy unit

UnitValueExact factor
joules3,600,000 J× 3,600,000
kilojoules3,600 kJ× 3,600
calories860,420.6501 cal× 860,420.650096
kilocalories860.4206501 kcal× 860.420650096
watt-hours1,000 Wh× 1,000
kilowatt-hours (as entered)1 kWh
British thermal units3,412.141633 BTU× 3,412.14163313
foot-pounds2,655,223.737 ft·lbf× 2,655,223.7374

Factors are entered by hand from NIST Special Publication 811 rather than derived from a units library, so the ones that terminate are exact rather than rounded.

How do you convert kilowatt-hours to calories?

  1. 1.Take the measurement in kilowatt-hours.
  2. 2.Multiply by 860420.65 — that is how many calories fit in one kilowatt-hour.
  3. 3.To go back the other way, divide by 860420.65, or multiply by 1.1622 × 10^-6.

Worked example: 25 kilowatt-hours to calories

Formula
kWh × 860420.65 = cal
Arithmetic
25 × 860420.65 = 21,510,516.2524 cal
Answer
25 kWh = 21,510,516.2524 cal

The factor is rounded for display; the figure above is computed from the full value.

Kilowatt-hours to calories conversion table

Kilowatt-hoursCalories
1 kWh860,420.650096 cal
2 kWh1,720,841.300192 cal
3 kWh2,581,261.950288 cal
4 kWh3,441,682.600384 cal
5 kWh4,302,103.25048 cal
6 kWh5,162,523.900576 cal
7 kWh6,022,944.550672 cal
8 kWh6,883,365.200768 cal
9 kWh7,743,785.850864 cal
10 kWh8,604,206.50096 cal
12 kWh10,325,047.801152 cal
15 kWh12,906,309.75144 cal
20 kWh17,208,413.00192 cal
25 kWh21,510,516.2524 cal
50 kWh43,021,032.5048 cal
100 kWh86,042,065.0096 cal
200 kWh172,084,130.0192 cal
300 kWh258,126,195.0288 cal
500 kWh430,210,325.048 cal
1000 kWh860,420,650.096 cal
2000 kWh1,720,841,300.192 cal
5000 kWh4,302,103,250.480001 cal
10000 kWh8,604,206,500.960001 cal

What is a kilowatt-hour?

A thousand watt-hours, and the unit every electricity bill is added up in. Exactly 3.6 megajoules, and the reason a 100 W bulb left on for ten hours costs one unit.

What is a calorie?

The thermochemical calorie: exactly 4.184 joules by definition. This is the small calorie — the one on a food label is a thousand of these, which is the single most common confusion in this group.

How many calories are in a kilowatt-hour?

One kilowatt-hour is 860420.65 calories. Going the other way, one calorie is 1.1622 × 10^-6 kilowatt-hours. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.

Every energy unit here

UnitSymbolOne of these is
JoulesJthe base unit
KilojouleskJ1000 joule
Caloriescal4.184 joule
Kilocalorieskcal4184 joule
Watt-hoursWh3600 joule
Kilowatt-hourskWh3600000 joule
British thermal unitsBTU1055.0559 joule
Foot-poundsft·lbf1.3558179 joule

Source: NIST Special Publication 811 — the thermochemical calorie is exactly 4.184 J

Questions people actually ask

How many calories are in a kilowatt-hour?
860420.65. The thermochemical calorie: exactly 4.184 joules by definition. This is the small calorie — the one on a food label is a thousand of these, which is the single most common confusion in this group.
How do I convert calories back to kilowatt-hours?
Divide by 860420.65, or multiply by 1.1622 × 10^-6 — they are the same operation.

Other energy conversions

Calories to kilowatt-hours — the same conversion the other way.

Calculators that work in energy