Energy Converter

Convert between energy units: joules, calories, watt-hours, BTU, and more.

4184

1 kilocalorie = 4184 joule

How to Use Energy Converter

1

Select energy units

Choose the source and target energy units from the dropdown menus. All common energy and heat units are available.

2

Enter the energy value

Type the energy amount you want to convert. The result updates instantly in real time as you type.

3

Copy or swap the result

Copy the converted energy value to your clipboard, or click swap to reverse the conversion direction.

About Energy Converter

Energy converter online — convert joules to calories, BTU to kilowatt-hours, and between all energy measurement units instantly for free. Supports joules, kilojoules, calories, kilocalories (food calories), BTU, kilowatt-hours, watt-hours, electron volts, and foot-pounds with high precision. Ideal for physics homework, nutrition label conversions, HVAC calculations, and electricity bill analysis. No signup, no ads — runs entirely in your browser.

Key Features

  • Convert between all common energy units including joules, kilojoules, calories, kilocalories, BTU, kWh, and electron volts
  • Real-time bidirectional conversion updates results instantly as you type any energy value
  • Differentiates between food calories (kcal) and scientific calories (cal) to avoid confusion
  • High precision calculations with multiple decimal places for physics, nutrition, and engineering
  • One-click unit swap to quickly reverse energy conversion direction between any two units
  • 100% free and private — all energy calculations happen in your browser with no data collection

Frequently Asked Questions

How to convert joules to calories online?
Enter the joules value and select calories as target. 1 joule equals approximately 0.2390 calories. For food calories (kcal), divide by 4,184.
How to convert BTU to kilowatt-hours?
Select BTU as source and kWh as target. 1 BTU equals approximately 0.000293 kWh. Common for HVAC and heating system calculations.
How to convert calories to joules?
Enter the calorie value and select joules. 1 calorie equals exactly 4.184 joules. Used in physics and chemistry calculations.
How to convert kilocalories to calories?
1 kilocalorie (kcal) equals exactly 1,000 calories. Food nutrition labels list energy in kcal, often misleadingly labeled as "calories."
How to convert kWh to joules?
Select kWh as source and joules as target. 1 kWh equals 3,600,000 joules. Useful for understanding electricity consumption in scientific terms.
How to convert BTU to calories?
Enter the BTU value and select calories. 1 BTU equals approximately 252 calories. Common for comparing heating and cooling energy ratings.
How to convert electron volts to joules?
Select eV as source and joules as target. 1 eV equals approximately 1.602 × 10⁻¹⁹ joules. Used in particle physics and quantum mechanics.
How to understand food calories vs scientific calories?
Food "calories" are actually kilocalories (kcal). 1 food calorie = 1 kcal = 1,000 scientific calories = 4,184 joules. Our converter handles both correctly.