What is a calorie?

Definition

cal

The calorie (cal) is the energy needed to raise 1 gram of water by 1°C, equal to approximately 4.184 joules.

Unit system

Heat & Food

Convert calories

Joules → Calories Kilojoules → Calories Megajoules → Calories Calories → Joules Calories → Kilojoules Calories → Megajoules Calories → Kilocalories Calories → Watt-hours

All energy units

Unit	Symbol	System
joules	J	SI / Metric
kilojoules	kJ	SI / Metric
megajoules	MJ	SI / Metric
calories	cal	Heat & Food
kilocalories	kcal	Heat & Food
watt-hours	Wh	Electrical
kilowatt-hours	kWh	Electrical
megawatt-hours	MWh	Electrical
BTU	BTU	Imperial
electronvolts	eV	Scientific
foot-pounds	ft·lb	Imperial
ergs	erg	Scientific