Convert calories to joules

Convert calories to joules by entering a value below.

1 cal (calories) = 4.184 J (joules)

How to Convert Calories to Joules

The calorie and joule are both units of energy. 1 calorie equals 4.184 joules. This means to convert calories to joules, you multiply by 4.184.

Formula

joules = calories × 4.184

Step-by-Step Example

Convert 5 cal to joules:

1
Convert 5 cal to joules

We need to convert calories to joules

2
Apply the formula

Since 1 cal = 4.184 J, multiply by 4.184

5 × 4.184 = 20.92

Answer

5 cal = 20.92 J

Calorie to Joule Conversion Table

Quick reference table for common calorie to joule conversions. Click any value for detailed calculation.

Calories (cal) Joules (J)
1 cal 4.184 J
2 cal 8.368 J
5 cal 20.92 J
10 cal 41.84 J
15 cal 62.76 J
20 cal 83.68 J
25 cal 104.6 J
50 cal 209.2 J
100 cal 418.4 J

About These Units

Calorie (cal)

A small calorie (cal) is the energy needed to raise 1 gram of water by 1°C, equal to 4.184 joules. Small calories are used in chemistry and physics. Note: food "Calories" (with capital C) are actually kilocalories. One calorie equals 0.003968 BTU.

Joule (J)

The joule (J) is the SI unit of energy equal to one watt-second or one newton-meter. Joules measure work, heat, and electrical energy. One joule equals approximately 0.239 calories. Lifting a 100g apple one meter requires about 1 joule. Named after physicist James Prescott Joule.

Frequently Asked Questions

How do I convert calories to joules?

To convert calories to joules, multiply the value by 4.184. For example, 10 cal = 41.84 J.

How many joules are in 1 calorie?

1 calorie equals 4.184 joules.

What is the formula for calories to joules?

The formula is: J = cal × 4.184.