Temperature conversion formulas

Summary

	kelvin	Celsius	Fahrenheit	Rankine	Delisle	Newton	Réaumur	Rømer
Absolute zero	0 K	-273.15 °C	-459.67 °F	0 °Ra	559,73 °De	-90.14 °N	-218.52 °Ré	-135.9 °Rø¸
Water freezing point	273.15 K	0 °C	32 °F	491.67 °Ra	150 °De	0 °N	0 °Ré	7.5 °Rø¸
Human body temperature	310.15 K	37 °C	98.6 °F	558.27 °Ra	94.5 °De	12.21 °N	29.6 °Ré	26.93 °Rø¸
Water boiling point	373.15 K	100 °C	212 °F	671.67 °Ra	0 °De	33 °N	80 °Ré	60 °Rø¸

From kelvin

Desired scale	Formula
Celsius	°C = K − 273.15
Fahrenheit	°F = K × 1.8 − 459.67
Rankine	°Ra = K × 1.8
Delisle	°De = (373.15 − K) × 1.5
Newton	°N = (K − 273.15) × 33/100
Réaumur	°Ré = (K − 273.15) × 0.8
Rømer	°Rø¸ = (K − 273.15) × 21/40 + 7.5

From Celsius

Desired scale	Formula
kelvin	K = °C + 273.15
Fahrenheit	°F = °C × 1.8 + 32
Rankine	°Ra = °C × 1.8 + 491.67
Delisle	°De = (100 − °C) × 1.5
Newton	°N = °C × 33/100
Réaumur	°Ré = °C × 0.8
Rømer	°Rø¸ = °C × 21/40 + 7.5

From Fahrenheit

Desired scale	Formula
kelvin	K = (°F + 459.67) / 1.8
Celsius	°C = (°F − 32) / 1.8
Rankine	°Ra = °F + 459.67
Delisle	°De = (212 − °F) × 5/6
Newton	°N = (°F − 32) × 11/60
Réaumur	°Ré = (°F − 32) / 2.25
Rømer	°Rø = (°F − 32) × 7/24 + 7.5

From Rankine

Desired scale	Formula
kelvin	K = °Ra / 1.8
Celsius	°C = °Ra / 1.8 - 273.15
Fahrenheit	°F = °Ra - 459.67
Delisle	°De = (671.67 − °Ra) × 5/6
Newton	°N = (°Ra − 491.67) × 11/60
Réaumur	°Ré = (°Ra / 1.8 + 273.15) × 0.8
Rømer	°Rø¸ = (°Ra − 491.67) × 7/24 + 7.5

From Delisle

Desired scale	Formula
kelvin	K = 373.15 − °De × 2/3
Celsius	°C = 100 − °De × 2/3
Fahrenheit	°F = 212 − °De × 1.2
Rankine	°Ra = 671.67 − °De × 1.2
Newton	°N = 33 − °De × 0.22
Réaumur	°Ré = 80 − °De × 8/15
Rømer	°Rø¸ = 60 − °De × 0.35

From Newton

Desired scale	Formula
kelvin	K = °N × 100/33 + 273.15
Celsius	°C = °N × 100/33
Fahrenheit	°F = °N &times 60/11 + 32
Rankine	°Ra = °N × 60/11 + 491.67
Delisle	°De = (33 − °N) × 50/11
Réaumur	°Ré = °N × 80/33
Rømer	°Rø¸ = °N × 35/22 + 7.5

From Réaumur

Desired scale	Formula
kelvin	K = °Ré / 0.8 + 273.15
Celsius	°C = °Ré / 0.8
Fahrenheit	°F = °Ré × 2.25 + 32
Rankine	°Ra = °Ré × 2.25 + 491.67
Delisle	°De = (80 − °Ré) × 1.875
Newton	°N = °Ré × 33/80
Rømer	°Rø¸ = °Ré × 21/32 + 7.5

From Rømer

Desired scale	Formula
kelvin	K = (°Rø¸ − 7.5) × 40/21 + 273.15
Celsius	°C = (°Rø¸ − 7.5) × 40/21
Fahrenheit	°F = (°Rø¸ − 7.5) × 24/7 + 32
Rankine	°Ra = (°Rø¸ − 7.5) × 24/7 + 491.67
Delisle	°De = (60 − °Rø¸) × 20/7
Newton	°N = (°Rø¸ − 7.5) × 22/35
Réaumur	°Ré = (°Rø¸ − 7.5) × 32/21