EnergyBtu to Kilojoules

BTU to Kilojoules

Snapshot

1 BTU equals 1.055056 Kilojoules. Conversion Encyclopedia uses the same fixed conversion basis across the calculator, common values, and reverse page for this page.

Reference basis: This conversion uses exact joule-based energy definitions.
Example: For 5 BTU, the result equals 5.275279 Kilojoules.
Use the reverse page if you need the opposite direction with the same basis.

Use the interactive calculator below for custom values and the common-value table for quick checks.

Interactive conversion

Converter Calculator

1.055056 Kilojoules (kJ)

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Machine access

Available to apps and AI agents

BTU to Kilojoules can be requested through Conversion Encyclopedia's structured interfaces by software and compatible AI agents. The identifiers below select the same calculation as the calculator.

Machine-readable identifiers

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

The JSON API and OpenAPI specification use the identifiers to reach the conversion engine. WebMCP lets compatible AI agents request the same calculation.

Example API request and response

POST /api/v1/convert

Request

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

Essential response

{
  "ok": true,
  "conversion": {
    "family": "energy",
    "value": 1,
    "from": "btu",
    "to": "kilojoules",
    "result": {
      "raw": 1.05505585262,
      "display": "1.055056"
    },
    "canonicalPath": "/energy/btu-to-kilojoules/"
  }
}

Full API documentation

Explanation

Formula: Kilojoules = BTU × 1.055056. Why: calories, kilocalories, and BTU each use fixed joule equivalents, so the route moves through joules and preserves one deterministic factor.

BTU (BTU): a thermal energy unit with a fixed joule equivalent, common in HVAC, heating, and thermal-system references.

Kilojoules (kJ): an energy unit equal to 1,000 joules, common in science, engineering, and nutritional labeling.

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

This conversion is purely multiplicative because both units reduce through joules using fixed energy definitions with no offset.

Method & Reference

Method basis: exact conversion formula shown in Snapshot.
Applied factor: 1 BTU = 1.055056 Kilojoules (using exact joule-based energy definitions).
Consistency rule: calculator output and table values use the same constants and rounding policy.

Common Conversion Values

BTU (BTU)	Kilojoules (kJ)
1	1.055056
5	5.275279
10	10.550559
100	105.505585
1,000	1,055.055853
3,600	3,798.201069
10,000	10,550.558526
1,000,000	1,055,055.85262

Questions & answers

Frequently Asked Questions

What is 1 btu in kilojoules?

1 BTU equals 1.055056 Kilojoules on this page.

Does this BTU to Kilojoules page use fixed joule equivalents for thermal units?

Yes. Calories, kilocalories, and BTU each use fixed joule equivalents on this page, so thermal and nutritional energy comparisons stay consistent across the direct answer, calculator, and table.

When would I convert btu to kilojoules?