Energy Converter
The energy converter translates between scientific, food, electricity and heating units. Joules and kilojoules are common in physics and nutrition labels, kilocalories describe food energy, kilowatt-hours appear on electricity bills, BTU is common in heating and cooling, and electron volts are used at atomic scales. Enter a value once and switch units live without recalculating manually.
Energy Scale
How to Use
- Type the number you want to convert in the Value field at the top.
- Select the unit you are converting from in the left dropdown.
- Select the unit you want to convert to in the right dropdown.
- Read the live result below; there is no calculate button.
- Use the Swap button to reverse the conversion direction instantly.
Energy in Everyday Activities
| Activity / Food | Energy | Equivalent in kcal |
|---|---|---|
| 1 slice bread | 250 kJ | 60 kcal |
| 1 cup cooked rice | 840 kJ | 200 kcal |
| 1 hour walking | 1000 kJ | 240 kcal |
| 1 hour cycling | 2000 kJ | 480 kcal |
| 1 litre petrol | 34 MJ | 8130 kcal |
| 1 kWh electricity | 3.6 MJ | 860 kcal |
| Adult daily need | 8700 kJ | 2000 kcal |
| 100g chocolate | 2200 kJ | 526 kcal |
FAQ
What is the difference between a calorie (cal) and a food Calorie (kcal)?
One food Calorie is one kilocalorie, equal to 1000 small calories or 4184 joules.
What is a kilowatt-hour and how is it used for electricity bills?
A kilowatt-hour is the energy used by 1000 watts running for one hour. Electricity bills commonly charge per kWh.
What is a BTU and where is it used?
BTU stands for British thermal unit and is often used for air conditioners, heaters and fuel energy.
How many joules are in a kilocalorie?
One kilocalorie equals 4184 joules.
What is the difference between energy and power?
Energy is the total amount of work or heat. Power is the rate at which energy is used or produced.