This is a collection of temperature conversion formulas and comparisons among eight different temperature scales, several of which have long been obsolete.

Temperatures on scales that either do not share a numeric zero or are nonlinearly related cannot correctly be mathematically equated (related using the symbol =), and thus temperatures on different scales are more correctly described as corresponding (related using the symbol ≘).[citation needed]

Conversion calculator

Calculator for temperature conversion
CelsiusFahrenheitKelvinRankineDelisleNewtonRéaumurRømer
032273.15491.67150007.5

Celsius scale

Temperature conversions
from Celsiusto Celsius
Kelvinx °C ≘ (x + 273.15) Kx K ≘ (x − 273.15) °C
Fahrenheitx °C ≘ (x × ⁠9/5⁠ + 32) °Fx °F ≘ (x − 32) × ⁠5/9⁠ °C
Rankinex °C ≘ (x + 273.15) × ⁠9/5⁠ °Rx °R ≘ (x − 491.67) × ⁠5/9⁠ °C

Kelvin scale

Temperature conversions
from Kelvinto Kelvin
Celsiusx K ≘ (x − 273.15) °Cx °C ≘ (x + 273.15) K
Fahrenheitx K ≘ (x × ⁠9/5⁠ − 459.67) °Fx °F ≘ (x + 459.67) × ⁠5/9⁠ K
Rankinex K ≘ x × ⁠9/5⁠ °Rx °R ≘ x × ⁠5/9⁠ K

Fahrenheit scale

Temperature conversions
from Fahrenheitto Fahrenheit
Celsiusx °F ≘ (x − 32) × ⁠5/9⁠ °Cx °C ≘ (x × ⁠9/5⁠ + 32) °F
Kelvinx °F ≘ (x + 459.67) × ⁠5/9⁠ Kx K ≘ (x × ⁠9/5⁠ − 459.67) °F
Rankinex °F ≘ (x + 459.67) °Rx °R ≘ (x − 459.67) °F

Rankine scale

Temperature conversions
from Rankineto Rankine
Celsiusx °R ≘ (x − 491.67) × ⁠5/9⁠ °Cx °C ≘ (x + 273.15) × ⁠9/5⁠ °R
Kelvinx °R ≘ x × ⁠5/9⁠ Kx K ≘ x × ⁠9/5⁠ °R
Fahrenheitx °R ≘ (x − 459.67) °Fx °F ≘ (x + 459.67) °R

Delisle scale

Temperature conversions
from Delisleto Delisle
Celsiusx °De ≘ (100 − x × ⁠2/3⁠) °Cx °C ≘ (100 − x) × ⁠3/2⁠ °De
Kelvinx °De ≘ (373.15 − x × ⁠2/3⁠) Kx K ≘ (373.15 − x) × ⁠3/2⁠ °De
Fahrenheitx °De ≘ (212 − x × ⁠6/5⁠) °Fx °F ≘ (212 − x) × ⁠5/6⁠ °De
Rankinex °De ≘ (671.67 − x × ⁠6/5⁠) °Rx °R ≘ (671.67 − x) × ⁠5/6⁠ °De

Newton scale

Temperature conversions
from Newtonto Newton
Celsiusx °N ≘ x × ⁠100/33⁠ °Cx °C ≘ x × ⁠33/100⁠ °N
Kelvinx °N ≘ (x × ⁠100/33⁠ + 273.15) Kx K ≘ (x − 273.15) × ⁠33/100⁠ °N
Fahrenheitx °N ≘ (x × ⁠60/11⁠ + 32) °Fx °F ≘ (x − 32) × ⁠11/60⁠ °N
Rankinex °N ≘ (⁠60/11⁠ x + 491.67) °Rx °R ≘ (x − 491.67) × ⁠11/60⁠ °N

Réaumur scale

Temperature conversions
from Réaumurto Réaumur
Celsiusx °Ré ≘ x × ⁠5/4⁠ °Cx °C ≘ x × ⁠4/5⁠ °Ré
Kelvinx °Ré ≘ (x × ⁠5/4⁠ + 273.15) Kx K ≘ (x − 273.15) × ⁠4/5⁠ °Ré
Fahrenheitx °Ré ≘ (x × ⁠9/4⁠ + 32) °Fx °F ≘ (x − 32) × ⁠4/9⁠ °Ré
Rankinex °Ré ≘ (x × ⁠9/4⁠ + 491.67) °Rx °R ≘ (x − 491.67) × ⁠4/9⁠ °Ré

Rømer scale

Temperature conversions
from Rømerto Rømer
Celsiusx °Rø ≘ (x − 7.5) × ⁠40/21⁠ °Cx °C ≘ (x × ⁠21/40⁠ + 7.5) °Rø
Kelvinx °Rø ≘ ((x − 7.5) × ⁠40/21⁠ + 273.15) Kx K ≘ ((x − 273.15) × ⁠21/40⁠ + 7.5) °Rø
Fahrenheitx °Rø ≘ ((x − 7.5) × ⁠24/7⁠ + 32) °Fx °F ≘ ((x − 32) × ⁠7/24⁠ + 7.5) °Rø
Rankinex °Rø ≘ ((x − 7.5) × ⁠24/7⁠ + 491.67) °Rx °R ≘ ((x − 491.67) × ⁠7/24⁠ + 7.5) °Rø

Comparison values chart

CelsiusFahrenheitKelvinRankineDelisleNewtonRéaumurRømer
500.00932.00773.151391.67−600.00165.00400.00270.00
490.00914.00763.151373.67−585.00161.70392.00264.75
480.00896.00753.151355.67−570.00158.40384.00259.50
470.00878.00743.151337.67−555.00155.10376.00254.25
460.00860.00733.151319.67−540.00151.80368.00249.00
450.00842.00723.151301.67−525.00148.50360.00243.75
440.00824.00713.151283.67−510.00145.20352.00238.50
430.00806.00703.151265.67−495.00141.90344.00233.25
420.00788.00693.151247.67−480.00138.60336.00228.00
410.00770.00683.151229.67−465.00135.30328.00222.75
400.00752.00673.151211.67−450.00132.00320.00217.50
390.00734.00663.151193.67−435.00128.70312.00212.25
380.00716.00653.151175.67−420.00125.40304.00207.00
370.00698.00643.151157.67−405.00122.10296.00201.75
360.00680.00633.151139.67−390.00118.80288.00196.50
350.00662.00623.151121.67−375.00115.50280.00191.25
340.00644.00613.151103.67−360.00112.20272.00186.00
330.00626.00603.151085.67−345.00108.90264.00180.75
320.00608.00593.151067.67−330.00105.60256.00175.50
310.00590.00583.151049.67−315.00102.30248.00170.25
300.00572.00573.151031.67−300.0099.00240.00165.00
290.00554.00563.151013.67−285.0095.70232.00159.75
280.00536.00553.15995.67−270.0092.40224.00154.50
270.00518.00543.15977.67−255.0089.10216.00149.25
260.00500.00533.15959.67−240.0085.80208.00144.00
250.00482.00523.15941.67−225.0082.50200.00138.75
240.00464.00513.15923.67−210.0079.20192.00133.50
230.00446.00503.15905.67−195.0075.90184.00128.25
220.00428.00493.15887.67−180.0072.60176.00123.00
210.00410.00483.15869.67−165.0069.30168.00117.75
200.00392.00473.15851.67−150.0066.00160.00112.50
190.00374.00463.15833.67−135.0062.70152.00107.25
180.00356.00453.15815.67−120.0059.40144.00102.00
170.00338.00443.15797.67−105.0056.10136.0096.75
160.00320.00433.15779.67−90.0052.80128.0091.50
150.00302.00423.15761.67−75.0049.50120.0086.25
140.00284.00413.15743.67−60.0046.20112.0081.00
130.00266.00403.15725.67−45.0042.90104.0075.75
120.00248.00393.15707.67−30.0039.6096.0070.50
110.00230.00383.15689.67−15.0036.3088.0065.25
100.00212.00373.15671.670.0033.0080.0060.00
90.00194.00363.15653.6715.0029.7072.0054.75
80.00176.00353.15635.6730.0026.4064.0049.50
70.00158.00343.15617.6745.0023.1056.0044.25
60.00140.00333.15599.6760.0019.8048.0039.00
50.00122.00323.15581.6775.0016.5040.0033.75
40.00104.00313.15563.6790.0013.2032.0028.50
30.0086.00303.15545.67105.009.9024.0023.25
20.0068.00293.15527.67120.006.6016.0018.00
10.0050.00283.15509.67135.003.308.0012.75
0.0032.00273.15491.67150.000.000.007.50
−10.0014.00263.15473.67165.00−3.30−8.002.25
−14.266.29258.86465.96171.43−4.71−11.430.00
−17.780.00255.37459.67176.67−5.87−14.22−1.83
−20.00−4.00253.15455.67180.00−6.60−16.00−3.00
−30.00−22.00243.15437.67195.00−9.90−24.00−8.25
−40.00−40.00233.15419.67210.00−13.20−32.00−13.50
−50.00−58.00223.15401.67225.00−16.50−40.00−18.75
−60.00−76.00213.15383.67240.00−19.80−48.00−24.00
−70.00−94.00203.15365.67255.00−23.10−56.00−29.25
−80.00−112.00193.15347.67270.00−26.40−64.00−34.50
−90.00−130.00183.15329.67285.00−29.70−72.00−39.75
−100.00−148.00173.15311.67300.00−33.00−80.00−45.00
−110.00−166.00163.15293.67315.00−36.30−88.00−50.25
−120.00−184.00153.15275.67330.00−39.60−96.00−55.50
−130.00−202.00143.15257.67345.00−42.90−104.00−60.75
−140.00−220.00133.15239.67360.00−46.20−112.00−66.00
−150.00−238.00123.15221.67375.00−49.50−120.00−71.25
−160.00−256.00113.15203.67390.00−52.80−128.00−76.50
−170.00−274.00103.15185.67405.00−56.10−136.00−81.75
−180.00−292.0093.15167.67420.00−59.40−144.00−87.00
−190.00−310.0083.15149.67435.00−62.70−152.00−92.25
−200.00−328.0073.15131.67450.00−66.00−160.00−97.50
−210.00−346.0063.15113.67465.00−69.30−168.00−102.75
−220.00−364.0053.1595.67480.00−72.60−176.00−108.00
−230.00−382.0043.1577.67495.00−75.90−184.00−113.25
−240.00−400.0033.1559.67510.00−79.20−192.00−118.50
−250.00−418.0023.1541.67525.00−82.50−200.00−123.75
−260.00−436.0013.1523.67540.00−85.80−208.00−129.00
−270.00−454.003.155.67555.00−89.10−216.00−134.25
−273.15−459.670.000.00559.725−90.1395−218.52−135.90375
CelsiusFahrenheitKelvinRankineDelisleNewtonRéaumurRømer

Comparison of temperature scales

Comparison of temperature scales
CommentKelvinCelsiusFahrenheitRankineDelisleNewtonRéaumurRømer
Absolute zero0.00−273.15−459.670.00559.73−90.14−218.52−135.90
Lowest recorded surface temperature on Earth184−89.2−128.6331284−29−71−39
Fahrenheit's ice/salt mixture255.37−17.780.00459.67176.67−5.87−14.22−1.83
Ice melts (at standard pressure)273.150.0032.00491.67150.000.000.007.50
Triple point of water273.160.0132.018491.688149.9850.00330.0087.50525
Average surface temperature on Earth288155951912851215
Average human body temperature*310379855895122927
Highest recorded surface temperature on Earth33158136.459663194638
Water boils (at standard pressure)373.133999.9839211.97102671.641020.0033.0080.0060.00
Titanium melts1941166830343494−23525501334883
The surface of the Sun58005500990010400−8100180044002900

* Normal human body temperature is 36.8 °C ±0.7 °C, or 98.2 °F ±1.3 °F. The commonly given value 98.6 °F is simply the exact conversion of the nineteenth-century German standard of 37 °C. Since it does not list an acceptable range, it could therefore be said to have excess (invalid) precision.

Some numbers in this table have been rounded.

Graphical representation

Rankine (°R)
Kelvin (K)
Fahrenheit (°F)
Celsius (°C) Réaumur (°Ré) Rømer (°Rø) Newton (°N)
Delisle (°D)
Absolute zeroLowest recorded surface temperature on EarthFahrenheit's ice/water/salt mixtureMelting point of ice (at standard pressure)Average surface temperature on Earth (15 °C)Average human body temperature (37 °C)Highest recorded surface temperature on EarthBoiling point of water (at standard pressure)

Conversion table between the different temperature units

Converting units of temperature differences

Converting units of temperature differences (also referred to as temperature deltas) is not the same as converting absolute temperature values, and different formulae must be used.

To convert a delta temperature from degrees Fahrenheit to degrees Celsius, the formula is {ΔT}°F = ⁠9/5⁠{ΔT}°C.

To convert a delta temperature from degrees Celsius to kelvin, it is 1:1 ({ΔT}°C = {ΔT}K).

See also

Notes and references