Convert rankine to celsius easily.

Ever wondered how to switch between the Rankine and Celsius temperature scales? Maybe you’re an engineering student staring at a thermodynamics problem, or perhaps you’ve stumbled upon a vintage scientific paper using °R. Either way, converting Rankine to Celsius isn’t as intimidating as it seems. Let’s break it down step by step, with real world examples and a touch of historical flair.

Unit definitions

What is a rankine (°R)?

Rankine is an absolute temperature scale, meaning it starts at absolute zero (the coldest possible temperature). Its degrees are the same size as Fahrenheit degrees, making it a cousin of the Kelvin scale.

• Symbol: °R
• Common uses: U.S. aerospace, mechanical engineering, and thermodynamics.
• Definition: 0°R = absolute zero (-459.67°F).

What is a celsius (°C)?

Celsius is the most widely used temperature scale globally, based on water’s phase changes. It’s relative, not absolute, so it’s anchored to water’s freezing and boiling points.

• Symbol: °C
• Common uses: Weather forecasts, cooking, scientific research outside the U.S.
• Definition: 0°C = water freezes, 100°C = water boils (at sea level).

Conversion formula

To convert Rankine to Celsius, use this formula:
C = (R − 491.67) × 5/9

Here’s why: Since Rankine and Fahrenheit share degree sizes, subtracting 491.67 (which is 459.67°F + 32°F) bridges the gap to Celsius. Multiply by 5/9 to complete the shift from Fahrenheit to Celsius.

Example calculations

1. 500°R to Celsius
   (500 − 491.67) = 8.33
   8.33 × 5/9 ≈ 4.63°C
2. 600°R to Celsius
   (600 − 491.67) = 108.33
   108.33 × 5/9 ≈ 60.18°C

Conversion tables

Rankine to celsius

Celsius to rankine

Historical background

The Rankine scale was proposed by Scottish engineer William John Macquorn Rankine in 1859. It mirrored Kelvin’s absolute scale but catered to Fahrenheit users—kind of a compromise between imperial and scientific needs. Meanwhile, Celsius, originally called “centigrade,” was developed by Swedish astronomer Anders Celsius in 1742. Fun fact: Celsius initially set boiling water at 0° and freezing at 100°, but it was flipped after his death !

Interesting facts?

1. Absolute zero in Rankine is 0°R, just like in Kelvin (0K).
2. Space shuttle legacy: NASA’s space shuttle program used Rankine in some subsystems.
3. Celsius rebrand: The term “centigrade” was replaced by “Celsius” in 1948 to honor its creator.
4. Rankine’s niche: Outside the U.S., Rankine is rarely used—most countries prefer Kelvin.
5. Close cousins: A 1°R difference equals a 1°F difference, just like 1K = 1°C.

FAQ