Historical Temperature ScalesFahrenheit to Reaumur

Fahrenheit to Réaumur

Methodology·How We Verify

Snapshot

1 Fahrenheit equals -13.777778 Réaumur.

Reference basis: This conversion uses a scale-and-offset equation (°Ré = (°F - 32) / 2.25).
Example: For 20 Fahrenheit, the converted value equals -5.333333 Réaumur.

Interactive conversion

Converter Calculator

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

-13.777778 Réaumur (°Ré)

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API and AI agent access

Fahrenheit to Réaumur.

Machine-readable identifiers

Conversion family: historical-temperature-scales
Source unit: fahrenheit
Target unit: reaumur

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": "historical-temperature-scales",
  "value": 1,
  "from": "fahrenheit",
  "to": "reaumur"
}

Essential response

{
  "ok": true,
  "conversion": {
    "family": "historical-temperature-scales",
    "value": 1,
    "from": "fahrenheit",
    "to": "reaumur",
    "result": {
      "raw": -13.777777777777779,
      "display": "-13.777778"
    },
    "canonicalPath": "/historical-temperature-scales/fahrenheit-to-reaumur/"
  }
}

API, OpenAPI and WebMCP documentation

Explanation

Use the exact affine transform: subtract 32 from Fahrenheit, then divide by 2.25.

Method & Reference

Method basis: exact affine formula (scale + offset) shown in Snapshot.
Equation reference: °Ré = (°F - 32) / 2.25
Consistency rule: forward and reverse pages use inverse equations to preserve scale reference points.

Reference note

This Fahrenheit to Réaumur page uses explicit historical scale equations (scale + offset), not a simple multiplier.

Historical temperature scales are reconstructed from standard reference definitions.
Forward and reverse directions use inverse formulas, so each direction has its own dedicated page.

Common Conversion Values

Fahrenheit (°F)	Réaumur (°Ré)
-40	-32
0	-14.222222
20	-5.333333
32	0
80	21.333333
100	30.222222

Questions & answers

Frequently Asked Questions

What is 1 Fahrenheit in Réaumur?

1 Fahrenheit equals -13.777778 Réaumur on this page.

What equation does this Fahrenheit to Réaumur page use?

This page uses °Ré = (°F - 32) / 2.25, and the same equation drives the direct answer, calculator, table, and FAQ.

Is there a reverse page for Réaumur to Fahrenheit?

Yes. The reverse direction has its own page at °Ré to °F, where the inverse equation is used so the mirror route stays numerically aligned.