# Degrees Rankine to Kelvin (°R to K)

> Convert degrees Rankine to kelvin with the formula K = °R × 5/9. Conversion table and worked examples, with JSON API and MCP access.

- Page id: `rankine-to-kelvin` · Quantity: Temperature (`temperature`, base unit K) · Tool: `convert_units`
- Canonical page: https://tttkmbb.com/conversion/rankine-to-kelvin · This document: https://tttkmbb.com/conversion/rankine-to-kelvin.md · JSON: https://tttkmbb.com/conversion/rankine-to-kelvin.json (add `?value=` for a result)

## Formula

- `K = °R × 5/9`
- `K = °R × 5/9`
- Reverse: `°R = K × 9/5`

Non-linear conversion: apply the formula directly; there is no single multiplication factor.

## Worked examples

- 300 °R = 166.667 K
- 273.15 °R = 151.75 K
- 0 °R = 0 K

## Conversion table

| Degrees Rankine (°R) | Kelvin (K) |
| --- | --- |
| 0 | 0 |
| 50 | 27.7778 |
| 100 | 55.5556 |
| 150 | 83.3333 |
| 200 | 111.111 |
| 250 | 138.889 |
| 273.15 | 151.75 |
| 293.15 | 162.861 |
| 300 | 166.667 |
| 310 | 172.222 |
| 350 | 194.444 |
| 373.15 | 207.306 |
| 400 | 222.222 |
| 500 | 277.778 |
| 600 | 333.333 |
| 800 | 444.444 |
| 1000 | 555.556 |
| 1500 | 833.333 |
| 2000 | 1111.11 |
| 5000 | 2777.78 |

## API

- `GET https://tttkmbb.com/api/v1/convert?value=300&from_unit=R&to_unit=K` → unified JSON envelope with `result.values.result`, `formula`, `factor`, `sources`, `freshness`
- MCP: server `https://tttkmbb.com/mcp`, tool `convert_units` with `{"value":300,"from_unit":"R","to_unit":"K"}`
- All temperature units: https://tttkmbb.com/api/v1/units?quantity=temperature · full converter: [Temperature Converter](https://tttkmbb.com/conversion/temperature.md)
- Authentication: none. Freshness: `static` (fixed conversion factors).

## FAQ

**What is the formula to convert degrees Rankine to kelvin?**

K = °R × 5/9. For example, 300 °R = 166.667 K.

**How do I convert kelvin back to degrees Rankine?**

°R = K × 9/5; the kelvin-to-degrees Rankine page applies it directly.

**Why is there no single multiplication factor?**

Temperature scales have different zero points, so the conversion is an affine formula (scale and offset), not a plain multiplication.

## Related conversions

- [Kelvin to degrees Rankine](https://tttkmbb.com/conversion/kelvin-to-rankine.md) (reverse)
- [Degrees Celsius to Degrees Fahrenheit](https://tttkmbb.com/conversion/celsius-to-fahrenheit.md)
- [Degrees Fahrenheit to Degrees Celsius](https://tttkmbb.com/conversion/fahrenheit-to-celsius.md)
- [Degrees Celsius to Kelvin](https://tttkmbb.com/conversion/celsius-to-kelvin.md)
- [Kelvin to Degrees Celsius](https://tttkmbb.com/conversion/kelvin-to-celsius.md)
- [Degrees Fahrenheit to Kelvin](https://tttkmbb.com/conversion/fahrenheit-to-kelvin.md)
- [Kelvin to Degrees Fahrenheit](https://tttkmbb.com/conversion/kelvin-to-fahrenheit.md)
- [Degrees Fahrenheit to Degrees Rankine](https://tttkmbb.com/conversion/fahrenheit-to-rankine.md)
- [Degrees Rankine to Degrees Fahrenheit](https://tttkmbb.com/conversion/rankine-to-fahrenheit.md)

## Data Sources

- NIST Special Publication 811 – Guide for the Use of the International System of Units (SI), Appendix B conversion factors — https://www.nist.gov/pml/special-publication-811 (standard, retrieved 2026-09-24)
- BIPM – The International System of Units (SI Brochure, 9th edition) — https://www.bipm.org/en/publications/si-brochure (standard, retrieved 2026-09-24)
- Wikipedia – Conversion of units — https://en.wikipedia.org/wiki/Conversion_of_units (reference, retrieved 2026-09-24)