kcal to kJ Converter

Convert Kilocalories to Kilojoules instantly

Formula:

kJ = kcal × 4.184

1 kilocalorie = 4.184 kilojoules

🔗 Related Energy Converters

kJ → kcal kcal → cal cal → kcal J → kJ kJ → J cal → J J → cal ft-lb → Nm Nm → ft-lb All Converters

kcal to kJ (Kilocalories → Kilojoules)

1. Core Idea

1 kcal = 4.184 kJ. Multiply kcal by 4.184 (≈4.2 mental) to convert to kilojoules.

2. Formula

kJ = kcal × 4.184

kcal = kJ ÷ 4.184

4.184 is exact (thermochemical definition).

3. Quick Values

  • 25 kcal → 104.6 kJ
  • 50 kcal → 209.2 kJ
  • 75 kcal → 313.8 kJ
  • 100 kcal → 418.4 kJ
  • 250 kcal → 1046 kJ
  • 500 kcal → 2092 kJ
  • 1000 kcal → 4184 kJ
  • 2000 kcal → 8368 kJ

4. 3-Step Example

Convert 360 kcal to kJ

  1. Formula: kJ = kcal × 4.184
  2. Insert: 360 × 4.184
  3. = 1506.24 kJ (≈ 1506 kJ)

5. Where It’s Used

Food labeling (EU/AU/NZ), nutrition plans, sports dietetics, metabolic energy studies, recipe formulation.

6. Accuracy & Tips

  • Mental shortcut: kcal × 4 ≈ kJ (then add ~4%).
  • Round daily totals to nearest 10 kJ or whole kcal.
  • Consistency: use same precision across a label.
  • Reverse quickly: kJ ÷ 4 ≈ kcal (slight underestimate).

7. More Examples

kcalkJ
12.552.30
72301.25
185774.0
6402677.76

8. FAQ

Why 4.184 not 4.2?

4.184 is exact; 4.2 adds ~0.4% error—fine for estimates, not labels.

Fast back-conversion?

Divide kJ by 4 then add ~6% to adjust (since 4 vs 4.184).