Convert Rankine to Fahrenheit
Fahrenheit = Rankine − 459.67. Type any temperature below to convert rankine to fahrenheit both ways — it runs entirely in your browser.
Rankine to Fahrenheit formula
Temperature scales have different zero points, so the conversion is a multiply-and-add, not a single ratio:
Fahrenheit = Rankine − 459.67
To go the other way, Rankine = Fahrenheit + 459.67.
Worked example
Convert 540 °R to fahrenheit:
= 540 − 459.67 = 80.33 °F.
Common temperatures in Rankine and Fahrenheit
| Reference point | Rankine (°R) | Fahrenheit (°F) |
|---|---|---|
| Absolute zero | 0 | -459.67 |
| Freezing point of water | 491.67 | 32 |
| Refrigerator | 498.87 | 39.2 |
| Room temperature | 529.47 | 69.8 |
| Normal human body temperature | 558.27 | 98.6 |
| A hot summer day | 572.67 | 113 |
| Boiling point of water (sea level) | 671.67 | 212 |
About the Rankine and Fahrenheit scales
Rankine: The Rankine scale starts at absolute zero like Kelvin but uses the Fahrenheit-sized degree (0 °R = −459.67 °F). It appears in some US engineering and thermodynamics work.
Fahrenheit: Fahrenheit puts water’s freezing point at 32° and its boiling point at 212° — a 180-degree span. It is the everyday scale in the United States and a few other territories.
Sources
- NIST Special Publication 811 — Guide for the Use of the SI — publishes the defining relations between the temperature scales. Unlike every other conversion on this site these are affine, not a single multiplying factor: t/°C = (t/°F − 32)/1.8 and T/K = (T/°R)/1.8 are exact by definition, so the figures here are exact rather than rounded — the scales simply have different zero points as well as different degree sizes.
- BIPM — The International System of Units (SI Brochure) — the defining document for the SI, published by the International Bureau of Weights and Measures. It fixes the base unit that this conversion resolves to, which is why the factor here can be exact rather than approximate.
Frequently asked questions
- What is 540 °R in Fahrenheit?
- 540 °R = 80.33 °F.
- How do I convert Rankine to Fahrenheit?
- Use fahrenheit = rankine − 459.67. For example, 540 °R → 80.33 °F.
- How do I convert Fahrenheit back to Rankine?
- Reverse it: rankine = fahrenheit + 459.67.
- Why isn't converting Rankine to Fahrenheit just multiplication?
- Because the two scales start their zero at different temperatures, so after scaling by 1 you also subtract 459.67. Skipping that constant is the most common temperature-conversion mistake.