WeightStones to Kilograms

Stones to Kilograms

Updated: July 25, 2026 · Source: NIST Guide to the SI, Appendix B (Authoritative SI and U.S. customary conversion-factor reference.)

Methodology·How We Verify

Snapshot

1 stone equals exactly 6.35029318 kilograms. Conversion Encyclopedia uses the same fixed conversion basis across the calculator, common values, and reverse page for this page.

Reference basis: Multiply stone by 6.35029318 to obtain kilograms.
Example: For 10 stone, the result is 63.5029318 kilograms.
Source basis: NIST Guide to the SI, Appendix B.

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

Interactive conversion

Converter Calculator

6.35 Kilograms

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Machine access

Available to apps and AI agents

Stones to Kilograms 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: weight
Source unit: stone
Target unit: kilogram

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": "weight",
  "value": 1,
  "from": "stone",
  "to": "kilogram"
}

Essential response

{
  "ok": true,
  "conversion": {
    "family": "weight",
    "value": 1,
    "from": "stone",
    "to": "kilogram",
    "result": {
      "raw": 6.35029318,
      "display": "6.35"
    },
    "canonicalPath": "/weight/stones-to-kilograms/"
  }
}

Full API documentation

Explanation

One stone equals exactly 6.35029318 kilograms. Stone is still commonly used for body weight in the United Kingdom and Ireland, and it contains 14 avoirdupois pounds, so the kilogram value follows from the exact international pound definition.

Multiply stone by 6.35029318 to obtain kilograms.

Conversion Basis

Multiply stone by 6.35029318 to obtain kilograms.
For 10 stone, the result is 63.5029318 kilograms.
The snapshot, calculator, common values, and reverse route use the same conversion basis.
Source: NIST Guide to the SI, Appendix B (Authoritative SI and U.S. customary conversion-factor reference.)

Reference & Scope

The conversion uses 14 avoirdupois pounds per stone and the exact international pound-to-kilogram definition.

Values are calculated from one explicit conversion basis.
Displayed results are rounded only after the underlying calculation.
Real measured materials and ingredients can vary from the stated reference basis.
Source: NIST Guide to the SI, Appendix B (Authoritative SI and U.S. customary conversion-factor reference.)

Common Conversion Values

Stones	Kilograms
1	6.35
5	31.751
8	50.802
9	57.153
10	63.503
11	69.853
12	76.204
14	88.904

Questions & answers

Frequently Asked Questions

What is 1 stone in kilograms?

1 Stone equals 6.35 Kilograms on this page.

What definition does this Stones to Kilograms page use?

This route uses exact modern mass definitions anchored to the kilogram, so the factor stays consistent across the direct answer, calculator, table, and FAQ.

Is there a reverse Kilograms to Stones page?

Use the mirror Kilograms to Stones page to switch the direction while keeping the same fixed mass definitions.