Convert degrees Rankine to kelvins

1 °R=0.5556K

Use the converter below to change any degrees Rankine value into kelvins instantly — with formula, conversion table, and real-world examples.

You have

Equals

0.55556

Conversion formula

Forward

K = °R × 5/9

Reverse

°R = K × 9/5

These temperature formulas are exact — no approximation involved.

About both units

From

Rankine

°R

The Rankine scale is an absolute scale whose degree size matches Fahrenheit. Zero °R is absolute zero (−459.67 °F). It is used in some US engineering thermodynamics — mainly aerospace, power plants and propulsion — where Fahrenheit-based calculations need an absolute reference.

Real-world: Room temperature ≈ 527 °R. Water boils at 671.67 °R. US rocket-engine thermodynamics textbooks use Rankine.

Read full rankine reference →

Kelvin

The kelvin is the SI base unit of thermodynamic temperature. Its zero point is absolute zero — the theoretical coldest possible temperature. Water freezes at 273.15 K and boils at 373.15 K. Note: there is no "degree" symbol with kelvin, only "K".

Real-world: Room temperature ≈ 293 K. Water boils at 373 K. The Sun's surface is 5778 K. Deep space is about 2.7 K.

Read full kelvin reference →

Rankine to Kelvin conversion table

Common degrees Rankine to kelvins values for quick reference.

Rankine (°R)	Kelvin (K)
-40 °R	-22.2222 K
-20 °R	-11.1111 K
0 °R	0 K
10 °R	5.55556 K
20 °R	11.1111 K
25 °R	13.8889 K
30 °R	16.6667 K
37 °R	20.5556 K
100 °R	55.5556 K
200 °R	111.111 K

Tips & common mistakes

Quick tips

°R = °F + 459.67.
°R = K × 9/5. Identical absolute-zero anchor, different degree size.
Rankine is essentially obsolete outside specific US engineering specialisms.

Avoid these

Confusing Rankine with Réaumur (another historical scale).
Using Rankine outside US engineering contexts — nowhere else uses it.
Writing °R when Réaumur degree is meant — Réaumur is obsolete.

Frequently asked questions

How many kelvins in a rankine?

One rankine equals 0.5556 kelvins.

How do I convert degrees Rankine to kelvins?

Temperature conversion is non-linear. From Rankine to Kelvin use the specific formula — this tool applies it automatically.

What is 100 degrees Rankine in kelvins?

100 degrees Rankine equals 55.5556 kelvins.

Is a rankine bigger than a kelvin?

Temperature units compare by scale, not by size of one degree. Rankine and Kelvin use different zero points.

How to convert degrees Rankine to kelvins without a calculator?

Use the mental shortcut relevant to these temperature scales — but for accuracy always verify with a calculator.

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