Rankine to Kelvin
Rankine is an absolute temperature scale using Fahrenheit-sized degrees, starting at absolute zero, used occasionally in US engineering. Kelvin is the SI base unit of temperature, starting at absolute zero, used throughout science and astronomy. 1 °R equals ≈0.555556 K, so converting between them is a matter of multiplying by that fixed factor — type any value into the converter below and both sides update instantly as you type.
Both units belong to temperature, measured here against temperature's base unit (°C) — every other temperature unit on this site converts through that same reference point, which is why the table below can also be read as a quick cross-check against nearby values.
Formula
K = °R × ≈0.555556
°R = K × 1.8
Worked example: 5 °R × ≈0.555556 = ≈2.77778 K.
Conversion table
| Rankine (°R) | Kelvin (K) |
|---|---|
| 1 °R | ≈0.555556 K |
| 2 °R | ≈1.11111 K |
| 3 °R | ≈1.66667 K |
| 5 °R | ≈2.77778 K |
| 10 °R | ≈5.55556 K |
| 20 °R | ≈11.1111 K |
| 25 °R | ≈13.8889 K |
| 50 °R | ≈27.7778 K |
| 100 °R | ≈55.5556 K |
| 250 °R | ≈138.889 K |
| 500 °R | ≈277.778 K |
| 1,000 °R | ≈555.556 K |
Frequently asked
- How many Kelvin in a rankine?
- 1 °R equals ≈0.555556 K.
- How do I convert Rankine to Kelvin?
- Multiply the value in °R by ≈0.555556 to get K. The converter above does this instantly as you type.
- Is the conversion exact?
- Yes — Rankine and Kelvin are both defined by a fixed conversion factor to temperature's base unit (°C), so the result shown is exact to the precision displayed, not an approximation.