Rankine to Celsius (°R to °C)

Celsius to Rankine (Swap Units)


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Rankine to Celsius formula

°C =
ºR - 491.67
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More information: Celsius


A ºF version of the Kelvin scale. Based upon the definitions of the Fahrenheit scale and the experimental evidence that absolute zero is -459.67ºF


Rankine to Celsius formula

°C =
ºR - 491.67


Although initially defined by the freezing point of water (and later the melting point of ice), the Celsius scale is now officially a derived scale, defined in relation to the Kelvin temperature scale.

Zero on the Celsius scale (0°C) is now defined as the equivalent to 273.15K, with a temperature difference of 1 deg C equivalent to a difference of 1K, meaning the unit size in each scale is the same. This means that 100°C, previously defined as the boiling point of water, is now defined as the equivalent to 373.15K.

The Celsius scale is an interval system but not a ratio system, meaning it follows a relative scale but not an absolute scale. This can be seen because the temperature interval between 20°C and 30°C is the same as between 30°C and 40°C, but 40°C does not have twice the air heat energy of 20°C.

A temperature difference of 1 deg C is the equivalent of a temperature difference 1.8°F.


Rankine to Celsius table

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Rankine Celsius
0ºR -273.15°C
1ºR -272.59°C
2ºR -272.04°C
3ºR -271.48°C
4ºR -270.93°C
5ºR -270.37°C
6ºR -269.82°C
7ºR -269.26°C
8ºR -268.71°C
9ºR -268.15°C
10ºR -267.59°C
11ºR -267.04°C
12ºR -266.48°C
13ºR -265.93°C
14ºR -265.37°C
15ºR -264.82°C
16ºR -264.26°C
17ºR -263.71°C
18ºR -263.15°C
19ºR -262.59°C
Rankine Celsius
20ºR -262.04°C
21ºR -261.48°C
22ºR -260.93°C
23ºR -260.37°C
24ºR -259.82°C
25ºR -259.26°C
26ºR -258.71°C
27ºR -258.15°C
28ºR -257.59°C
29ºR -257.04°C
30ºR -256.48°C
31ºR -255.93°C
32ºR -255.37°C
33ºR -254.82°C
34ºR -254.26°C
35ºR -253.71°C
36ºR -253.15°C
37ºR -252.59°C
38ºR -252.04°C
39ºR -251.48°C
Rankine Celsius
40ºR -250.93°C
41ºR -250.37°C
42ºR -249.82°C
43ºR -249.26°C
44ºR -248.71°C
45ºR -248.15°C
46ºR -247.59°C
47ºR -247.04°C
48ºR -246.48°C
49ºR -245.93°C
50ºR -245.37°C
51ºR -244.82°C
52ºR -244.26°C
53ºR -243.71°C
54ºR -243.15°C
55ºR -242.59°C
56ºR -242.04°C
57ºR -241.48°C
58ºR -240.93°C
59ºR -240.37°C

Frequently Asked Questions

Is there a simple way to convert °R to °C in my head?

You can approximate by subtracting 490 from the Rankine value and dividing by 2.
Worked example:
550 °R - 490 = 60, 60 / 2 = 30 °C.
The actual answer is 32.406, so this method may be sufficient.

What is the formula to convert Rankine to Celsius?

°C = (°R - 491.67) / 1.8

... So, to convert 851.67 degrees Rankine to Celsius, we get:

(851.67 - 491.67) / 1.8

= 360 / 1.8

= 20°C

What does the Rankine and Celsius temperature range look like?

  • Absolute Zero: 0°R,  -273.15°C
  • Freezing point: 491.67°R,  0°C
  • Body Temperature: 558.27°R,  37°C
  • Boiling point: 671.67°R,  100°C

What is the definition of degrees Celsius?

The Celsius temperature range was originally defined by setting zero as the temperature at which water froze. Zero degrees C was later redefined as the temperature at which ice melts. The other point at which Celsius was set – 100 degrees Celsius – was defined as the boiling point of water.

Since its definition, the Celsius scale has been redefined in terms of degrees Kelvin. Zero degrees Celsius is now defined as 273.15K. As one degree Celsius is equal to one Kelvin, boiling point of water is equal to 273.15 + 100 = 373.15 Kelvin.

What is the defininition of degrees Rankine?

In the Rankine scale, absolute zero is 0 Rankine (0 °R), which is equivalent to -459.67 degrees Fahrenheit (-459.67 °F). The size of each degree Rankine is the same as each degree Fahrenheit, so the conversion between Rankine and Fahrenheit is straightforward

Why is converting Rankine to Celsius so difficult?

Because Rankine starts at 0, but Celsius starts at -273.15, and for every additional unit of heat energy the Celsius and Rankine scales add a different additional value. This makes it very hard to have an intuitive feeling for how an extra degree in one scale will affect the other scale.

What is the difference between Centigrade and Celsius?

Degrees Centigrade and degrees Celsius are the same thing. Degrees Celsius (invented by Anders Celsius) are sometimes called Centigrade, because the scale was defined between 0 and 100 degrees, hence centi-grade meaning a scale consisting of 1/100ths.

What are some common conversions from Rankine to Celsius?

0°R = -273.15°C
558.27°R,  37°C
671.67°R = 100°C

What are the most common misspellings of Celsius


What are common misspellings of Rankine


Can I do the opposite conversion - ie Celsius to Rankine - on this site?