Rankine to Celsius Converter

Quick Conversion: C = (R − 491.67) × 5/9

Rankine to Celsius Converter

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How to Convert Rankine to Celsius

The formula is:

C = (R − 491.67) × 5/9

Temperature conversion chart

To Fahrenheit To Celsius To Kelvin
From Fahrenheit (F) F (F - 32) × 5/9 (F - 32) × 5/9 + 273.15
From Celsius (C or o) (C × 9/5) + 32 C C + 273.15
From Kelvin (K) (K - 273.15) × 9/5 + 32 K - 273.15 K

Popular Temperature Conversions

Quick access to frequently searched temperature conversions:

0 Rankine→ °C459.67 Rankine→ °C491.67 Rankine→ °C671.67 Rankine→ °C

About the Rankine

Facts & Uses

  • Absolute temperature scale using Fahrenheit-sized degrees: 0 °R = absolute zero, 491.67 °R = water freezing, 671.67 °R = water boiling.
  • Used in US engineering disciplines — particularly thermodynamics, propulsion, HVAC, and aerospace — where absolute temperature is needed but Fahrenheit-sized increments are preferred.
  • Conversion is simple: °R = °F + 459.67 exactly. The relationship to Kelvin is K = °R × 5/9.
  • Found in steam tables, combustion analysis, and NIST reference data for the United States engineering community.

Curiosities

  • Proposed by William John Macquorn Rankine (1820-1872), Scottish engineer and physicist, in 1859 — eleven years after Kelvin proposed his absolute scale.
  • Rankine is the only widely-used absolute scale based on the Fahrenheit increment; its existence persists because US engineering standards predate metrication.
  • One Rankine degree equals one Fahrenheit degree in size (5/9 of a Kelvin), so temperature differences in Rankine = temperature differences in Fahrenheit.
  • Most modern textbooks and ISO standards have moved to Kelvin even in the US, but Rankine still appears in mechanical engineering reference tables and FAA aviation publications.

Sources

About the Celsius

Facts & Uses

  • Global standard for everyday temperature — used by 195 countries for weather, cooking, and science. Defined since 1954 by the Kelvin scale: 0 °C = 273.15 K exactly.
  • Anchored on water: 0 °C = freezing point, 100 °C = boiling point at 1 atm — the original Anders Celsius scale (1742) actually had these reversed.
  • Body temperature reference: ~37 °C normal, 38 °C+ low fever, 40 °C+ high fever requiring medical attention.
  • Cooking benchmarks: 180 °C moderate oven, 200 °C hot oven, 220 °C very hot/roasting, 0 °C ice water bath.

Curiosities

  • The original 1742 Celsius scale was inverted — 0° was boiling and 100° was freezing. Carl Linnaeus reversed it in 1745 after Celsius's death.
  • Adopted by the 13th CGPM in 1967-1968 as the official complementary unit to the Kelvin, with the relation T(°C) = T(K) − 273.15.
  • The only country still using Fahrenheit officially is the United States (plus a handful of small territories) — virtually all weather forecasts elsewhere use Celsius.
  • Approximate equivalents: 0 °C = 32 °F = 273.15 K; 100 °C = 212 °F = 373.15 K; −40 °C = −40 °F (the only crossover point).

Sources

Looking for the reverse? Convert Celsius to Rankine

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Conversion factors verified against NIST, BIPM, ITS-90 (International Temperature Scale) Defined by the absolute thermodynamic scale (Kelvin). Last reviewed: March 2026
Adilson Fernandes By Adilson Fernandes
Tiago Fernandes Reviewed by Tiago Fernandes