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.

Value

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

1Convert to joules first: 2000 kcal × 4184 = 8,368,000.0000 J
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.

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Key Points

Energy Converter is a free online unit conversion tool — open and use, no sign-up.
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Key capability: Joule, calorie, kWh and BTU conversions.
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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

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Open the page and fill in the input fields — results update automatically. Joule, calorie, kWh and BTU conversions.

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Related Guides

Source & Updates

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

Authoritative sources:

NIST SP 811 unit conversion

Last updated: 2026-08-07

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

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