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Energy converter

Energy and work, including the two different calories. 9 units, converted from one table of exact factors.

Worth knowing. The "calorie" on food packaging is a kilocalorie — a thousand of the calories physicists use. Both are in the table, which is where most confusion here comes from.

1 kilocalorie in every other energy unit

Computed by the same engine that runs the converter above, so these can never drift apart from it.

FromEqualsUnit
1 kilocalorie4,184joule (J)
1 kilocalorie4.184kilojoule (kJ)
1 kilocalorie1,000calorie (cal)
1 kilocalorie1.162222222watt hour (Wh)
1 kilocalorie0.001162222222kilowatt hour (kWh)
1 kilocalorie3.965666831BTU (BTU)
1 kilocalorie3,085.960033foot-pound (ft·lb)
1 kilocalorie2.611447397 × 10^+22electronvolt (eV)

What each unit actually is

Most converters give you a number and stop. Where a figure is exact by definition we say so, and where it is an average or shifts with conditions we say that too — that is usually the thing you needed to know.

UnitSymbolWhat it actually is
jouleJThe SI derived unit.
kilojoulekJExact. The energy unit on food labels outside the US.
caloriecalThe small or gram calorie. Exactly 4.184 J.
kilocaloriekcal1,000 small calories. THIS is the "calorie" on food labels and in diets — the everyday food calorie is a kilocalorie.
watt hourWhExact.
kilowatt hourkWhExact. The unit electricity is billed in.
BTUBTUThe international-table British thermal unit. Several slightly different BTUs exist; this is the standard one.
foot-poundft·lbExact.
electronvolteVExact since the 2019 SI redefinition.

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