EnergyKilocalories to Kilojoules

Kilocalories to Kilojoules

Methodology·How We Verify

Snapshot

1 Kilocalorie equals 4.184 Kilojoules.

Reference basis: This conversion uses exact joule-based energy definitions.
Example: For 5 Kilocalories, the result equals 20.92 Kilojoules.

Interactive conversion

Converter Calculator

Decimals: 1.5 or 1,5. Fractions: 1/2. Scientific notation: 1e3. Write 1000 without grouping separators.

4.184 Kilojoules (kJ)

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API and AI agent access

Kilocalories to Kilojoules.

Machine-readable identifiers

Conversion family: energy
Source unit: kilocalories
Target unit: kilojoules

Use these identifiers in the API request. Sources and model limits also apply to software clients.

Example API request and response

POST /api/v1/convert

Request

{
  "family": "energy",
  "value": 1,
  "from": "kilocalories",
  "to": "kilojoules"
}

Essential response

{
  "ok": true,
  "conversion": {
    "family": "energy",
    "value": 1,
    "from": "kilocalories",
    "to": "kilojoules",
    "result": {
      "raw": 4.184,
      "display": "4.184"
    },
    "canonicalPath": "/energy/kilocalories-to-kilojoules/"
  }
}

API, OpenAPI and WebMCP documentation

Explanation

Multiply by 4.184 (derived from joules) because 1 kcal = 4184 J and 1 kJ = 1000 J.

Method & Reference

Method basis: exact conversion formula shown in Snapshot.
Applied factor: 1 Kilocalorie = 4.184 Kilojoules (using exact joule-based energy definitions).
Consistency rule: calculator output and table values use the same constants and rounding policy.

Common Conversion Values

Kilocalories (kcal)	Kilojoules (kJ)
1	4.184
5	20.92
10	41.84
100	418.4
1000	4,184
3600	15,062.4
10000	41,840
1000000	4,184,000

Questions & answers

Frequently Asked Questions

What is 1 kilocalorie in kilojoules?

1 Kilocalorie equals 4.184 Kilojoules on this page.

When would I convert kilocalories to kilojoules?

This route is useful when translating thermal and nutritional energy values across calories, kilocalories, BTU, and joule-based references without mixing the underlying definitions.

How do I reverse Kilocalories to Kilojoules?

Use the mirror Kilojoules to Kilocalories route; it applies the inverse relationship with the same energy assumptions.