Kilocalorie to Joule Converter

1 Kilocalorie equals 4,184 Joule. To convert Kilocalorie to Joule, multiply the value by 4,184.

To convert Kilocalorie to Joule, multiply the value by 4,184. For example, 10 kcal = 40 J.

The Kilocalorie (kcal) is equal to 1,000 calories (4,184 joules), the standard unit for food energy — what is commonly called a "calorie" on nutrition labels.

The Joule (J) is the SI unit of energy, equal to one newton-meter, used in physics, engineering, and as the basis for all other energy units.

100 kcal equals 400 J. To convert Kilocalorie to Joule, multiply the value by 4,184.

The average US household uses about 30 kWh (kilowatt-hours) of electricity per day, or about 900 kWh per month. European households use less — a typical German household averages about 10–12 kWh per day. In joules, 1 kWh = 3,600,000 J (3.6 MJ).

Approximate food energy values: an apple ≈ 80 kcal, a slice of bread ≈ 80 kcal, a chicken breast (150 g) ≈ 165 kcal, a chocolate bar (50 g) ≈ 250 kcal, a Big Mac ≈ 550 kcal. Daily intake recommendations are typically 2,000 kcal for women and 2,500 kcal for men.

A 60-watt bulb running for 8 hours uses 60 W × 8 h = 480 Wh = 0.48 kWh. An equivalent LED bulb at 8–9 watts uses about 64–72 Wh for the same light output — roughly 85% less energy. In joules: 0.48 kWh = 1,728,000 J (1.73 MJ).

A standard AA alkaline battery stores about 3,000–3,500 mAh at 1.5V, which is roughly 16,000–19,000 joules (4.5–5.3 Wh). For comparison, a typical smartphone battery holds 10,000–15,000 J (2.8–4.2 Wh). A AA battery powers a TV remote for 6–12 months of normal use.

A typical family car engine produces 100–150 kW (134–201 hp) of peak power. At highway cruising speed, it uses about 15–25 kW continuously. In energy terms, gasoline contains about 32 MJ per liter (8.6 kWh/L). A full 50-liter tank holds about 1,600 MJ of chemical energy, though engines convert only 20–35% of that into motion.