Introducing the Energy Converter — Joules, kWh, BTU & More

Energy is measured in a dozen different units depending on who’s asking — joules in physics, calories in nutrition, kilowatt-hours on your electricity bill, BTU in heating and cooling. The new Energy Converter brings them all together so you can convert between any of them in one step.

What it does

• 11 units: joule, kilojoule, megajoule, calorie, kilocalorie, watt-hour, kilowatt-hour, BTU, therm, electronvolt, and foot-pound.
• Live conversion: type a value, pick your units, and the answer updates instantly — no Calculate button.
• Full reference table: see your value expressed in every unit at once.
• Swap & copy: reverse the direction in one click and copy the result.
• Client-side: fixed constants, no network — nothing is uploaded.

Why it matters

Energy conversion factors are irregular and easy to fumble — 4.184 here, 1,055 there, 3.6 million somewhere else. One slipped decimal can throw a result off by orders of magnitude. Letting the tool normalise everything through the joule removes the guesswork.

Learn more

For what each unit actually measures and how they relate, read the energy units guide. Then try the Energy Converter on your next bill or problem set.