🌡️ °C to °R — Celsius to Rankine Converter

Convert Celsius to Rankine. Used in US engineering thermodynamics and aerospace calculations.

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Formula °R = (°C + 273.15) × 9/5

All Celsius conversions

Unit	Name	Value
°F	Fahrenheit	33.8
K	Kelvin	274.15
°R	Rankine	493.47

Related Temperature conversions

°C → °F °F → °C °C → K K → °C °F → K

⚡ How to Convert Celsius to Rankine

Add 273.15 then multiply by 9/5. Formula: °R = (°C + 273.15) × 9/5. Example: (0 + 273.15) × 9/5 = 491.67°R. Reverse: °C = °R × 5/9 − 273.15.

Worked Examples

Example 1 — Aerospace — jet engine turbine inlet temperature

(1200°C + 273.15) × 9/5 = 2651.67°R

Jet engine turbine inlet temperatures reach ~1200°C. US aerospace engineers using Rankine-based thermodynamic tables (common in older NASA and FAA documentation) convert to 2651.67°R for specific heat and entropy calculations.

Example 2 — Chemical engineering — US refinery temperature

(500°C + 273.15) × 9/5 = 1391.67°R

US petroleum refineries frequently operate at ~500°C cracking temperatures. American chemical engineers using Rankine in legacy process simulation software (HYSYS, Aspen with Rankine settings) convert Celsius operating data to Rankine.

Example 3 — Thermodynamics — Carnot cycle with Rankine

(100°C + 273.15) × 9/5 = 671.67°R

US engineering students solving Carnot efficiency problems from Celsius data convert to Rankine when using American thermodynamic tables. The Carnot formula η = 1 − T_cold/T_hot works correctly with any absolute scale including Rankine.

Example 4 — Standards reference — water triple point

(0.01°C + 273.15) × 9/5 = 491.69°R

The triple point of water is 0.01°C. In US engineering standards documents that use Rankine, this appears as 491.69°R — a fundamental thermodynamic reference point for calibrating temperature sensors.

Celsius to Rankine — Reference Table

Celsius (°C)	Rankine (°R)	Real-world context
−273.15°C	0°R	Absolute zero
−17.78°C	459.67°R	Equivalent of 0°F
0°C	491.67°R	Water freezing point
20°C	527.67°R	Room temperature
37°C	558.27°R	Human body temperature
100°C	671.67°R	Water boiling point
500°C	1391.67°R	Refinery cracking temperature
1200°C	2651.67°R	Jet turbine inlet temperature

Mental Math Tricks for °C ↔ °R

Convert via Kelvin

Convert °C to K first (add 273.15), then K to °R (multiply by 9/5). Example: 100°C → 373.15 K → 373.15 × 1.8 = 671.67°R.

Multiply by 1.8 after adding 273

Since 9/5 = 1.8, the formula becomes: (°C + 273.15) × 1.8. Easier to type. (25 + 273.15) × 1.8 = 536.67°R.

Anchor: 0°C = 491.67°R

Memorise this anchor. Every degree Celsius adds 1.8°R. So 100°C = 491.67 + 180 = 671.67°R.

Check: result should be near 492 for everyday temps

Normal everyday temperatures (0°C to 40°C) convert to roughly 492°R to 564°R. Values far outside this range for everyday temps suggest an error.

Who Uses This Conversion?

Real professions and situations that need °C to °R conversion

✈️

Aerospace Engineers

US aerospace engineering uses Rankine in older thermodynamic tables, NASA technical reports and some FAA certification documents. Engineers working from Celsius data in international research papers convert to Rankine for legacy calculation workflows.

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US Chemical & Process Engineers

American process engineering software (legacy Aspen, HYSYS configurations) and older Perry's Chemical Engineers' Handbook editions use Rankine. Engineers converting Celsius process temperatures to Rankine for these tools do so routinely.

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US Engineering Students

American thermodynamics textbooks (Çengel & Boles, Smith-Van Ness) present problems in both Rankine and Kelvin. Students converting Celsius data from lab experiments to Rankine for homework problems encounter this regularly.

🔥

Combustion Engineers

Flame and furnace temperatures specified in Celsius by international equipment suppliers must be converted to Rankine for use in US combustion modelling software and heat transfer calculations.

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Standards & Metrology Engineers

ASTM, ASME and API standards in the US sometimes express temperature in Rankine. Metrology engineers converting SI Celsius calibration data to Rankine for compliance with these standards convert routinely.

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Thermodynamics Researchers

Research comparing Kelvin-based and Rankine-based thermodynamic property tables — common in comparative fluid dynamics studies — requires frequent conversion between Celsius and Rankine reference points.

All Celsius Conversions

Frequently Asked Questions

Add 273.15 then multiply by 9/5: °R = (°C + 273.15) × 9/5. Example: 0°C → (0+273.15)×9/5 = 491.67°R.

0°C equals 491.67°R — the freezing point of water on the Rankine scale.

100°C equals 671.67°R — the boiling point of water.

Absolute zero is 0°R = −273.15°C. The Rankine scale, like Kelvin, starts at absolute zero.

Rankine is primarily used in US engineering, particularly in aerospace, chemical engineering and thermodynamics textbooks. It is the Fahrenheit-based absolute temperature scale, analogous to how Kelvin is the Celsius-based absolute scale.

Both start at absolute zero. Rankine uses Fahrenheit-sized degrees (smaller than Celsius/Kelvin degrees), while Kelvin uses Celsius-sized degrees. 1 K = 1.8°R. To convert: K = °R × 5/9.

20°C equals 527.67°R. Formula: (20 + 273.15) × 9/5 = 527.67°R.

About Celsius and Rankine

Celsius (°C)

The Celsius scale (symbol: °C) was proposed by Anders Celsius in 1742 and is the international standard for everyday temperature measurement. Defined as 0°C = 273.15 K, it is used in science, medicine and daily life across most of the world.

The scale was renamed from "centigrade" to "Celsius" in 1948. Its degree interval is identical to the Kelvin — they differ only in their zero points. Celsius is the mandatory primary temperature unit in the EU, UK and most nations.

Rankine (°R)

The Rankine scale (symbol: °R) was proposed by Scottish engineer William John Macquorn Rankine in 1859. It is the Fahrenheit-based absolute temperature scale — just as Kelvin is the Celsius-based absolute scale. 0°R = absolute zero, and degree sizes match Fahrenheit (1°R = 1°F difference).

Rankine is primarily used in US engineering thermodynamics, particularly in legacy aerospace and chemical engineering calculations. The relationship to Kelvin is: K = °R × 5/9 (or °R = K × 9/5). While increasingly replaced by Kelvin in modern US engineering practice, Rankine remains in older textbooks, standards documents and legacy software. Rankine proposed his scale the same year he published his landmark textbook on applied mechanics.

Common use: Celsius-to-Rankine conversion is needed by US engineers using legacy thermodynamic software, ASTM/ASME standards documents, or older American engineering reference books that specify temperatures in Rankine. It bridges the international Celsius standard with the US Rankine convention.