Rankine to Kelvin Converter
Two-way converter: change Rankine to Kelvin or Kelvin to Rankine in one step.
Type a value in either field for an instant conversion
About converting Rankine and Kelvin
Rankine is the absolute-temperature scale paired with Fahrenheit, used in some US engineering fields. Kelvin is the SI base unit. The conversion is a simple division — both scales share the same zero point at absolute zero.
To convert Rankine to Kelvin, use the formula: K = °R × 5/9. The reverse formula handles the other direction automatically — type into either field.
Every calculation runs locally in your browser and updates instantly — nothing is uploaded, and the result appears the moment you type.
Why use this converter
Works both ways
Convert °R to K or K to °R by typing in either field.
Exact formula
Uses the standard temperature conversion formula with no shortcuts.
No install
Runs in any browser on phone or desktop, with no sign-up required.
Frequently asked questions
How do I convert Rankine to Kelvin?
Divide the Rankine value by 1.8 (or multiply by 5/9). Example: 540 °R = 540 / 1.8 = 300 K.
What is 0 °R in Kelvin?
0 °R equals 0 K — both scales start at absolute zero.
What is 491.67 °R in Kelvin?
491.67 °R = 273.15 K, the freezing point of water (= 32 °F).
Why use Rankine at all?
It lets engineers keep imperial units (Fahrenheit-sized steps) while working with an absolute scale, which is required by thermodynamic formulas.
Can the result be negative?
No. Both Kelvin and Rankine are absolute scales — the lowest possible value on either is zero.