Skip to main content

Energy Converter

Unit Converters

Joule, calorie, kWh and BTU conversions

Quick Answer

Energy Converter: Joule, calorie, kWh and BTU conversions. 1 kcal = 4184 J · 1 cal = 4.184 J.

Source unit

J — Joule8,368,000.0000
kJ — Kilojoule8,368.0000
kcal — Kilocalorie2,000.0000
cal — Calorie2,000,000.0000
Wh — Watt-hour2,324.4444
kWh — Kilowatt-hour2.3244
BTU — British thermal unit7,931.3025
hp·h — Horsepower-hour3.1166

Calculation steps

  1. 1Convert to joules first: 2000 kcal × 4184 = 8,368,000.0000 J
  2. 2Then divide by each unit's joule factor — e.g. ÷3.6×10⁶ for kWh, ÷4184 for kcal
1 kcal = 4.184 kJ · 1 kWh (electricity unit) = 860 kcal · 1 BTU ≈ 1.055 kJ. Chinese food labels use kJ while diets count kcal — divide the label value by 4.184 for calories. An adult's daily 2000 kcal ≈ 2.3 kWh, roughly one night of air conditioning.

Was this tool helpful?

How to Use

  1. Pick units: switch source and target units in the Energy Converter.
  2. Enter a value: results sync both ways instantly — no convert button needed.
  3. Use the reference table: common conversions are listed for instant lookup.
  4. Copy the result: copy the converted value with its unit.

Key Points

  • Energy Converter is a free online unit conversion tool — open and use, no sign-up.
  • All calculations run locally in your browser; your data never leaves the device.
  • Key capability: Joule, calorie, kWh and BTU conversions.
  • Results come with formulas and reference tables so you can verify every number.

Formula & How It Works

Energy conversion (base: joule)

1 kcal = 4184 J · 1 cal = 4.184 J
1 kWh = 3.6×10⁶ J = 860 kcal · 1 BTU = 1055.06 J
Food labels: kJ ÷ 4.184 = kcal

FAQ

How do I use the Energy Converter?
Open the page and fill in the input fields — results update automatically. Joule, calorie, kWh and BTU conversions.
Are the results accurate?
Yes. Standard formulas and conversion factors are used and verified.
Is it free? Do I need to sign up?
Completely free. No registration, login or download required.
Does it work on mobile?
Yes. The responsive design works on phones, tablets and desktops.
Is my data saved?
No. Everything runs locally in your browser.

Related Tools

Related Guides

Source & Updates

Based on SI conversion factors and international standards. Last updated: 2025-07

Authoritative sources:

Last updated:

Formulas and content on this page are reviewed by the YiJianSuan team. For reference only — official sources prevail.

Maintained and periodically reviewed by the YiJianSuan editorial team — review process in ourEditorial Policy.

Cite this page: YiJianSuan. Energy Converter[EB/OL]. https://www.yijiansuan.com/en/c/convert/energy-convert

Results provided by this tool are for reference only and do not constitute professional advice.