# Conversion of scales of temperature

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 ≘).

## Celsius scale

Temperature conversions :
| | from Celsius | to Celsius |
| Kelvin | x °C ≘ (x + 273.15) K | x K ≘ (x − 273.15) °C |
| Fahrenheit | x °C ≘ (x × ⁠9/5⁠ + 32) °F | x °F ≘ (x − 32) × ⁠5/9⁠ °C |
| Rankine | x °C ≘ (x + 273.15) × ⁠9/5⁠ °R | x °R ≘ (x − 491.67) × ⁠5/9⁠ °C |

## Kelvin scale

Temperature conversions :
| | from Kelvin | to Kelvin |
| Celsius | x K ≘ (x − 273.15) °C | x °C ≘ (x + 273.15) K |
| Fahrenheit | x K ≘ (x × ⁠9/5⁠ − 459.67) °F | x °F ≘ (x + 459.67) × ⁠5/9⁠ K |
| Rankine | x K ≘ x × ⁠9/5⁠ °R | x °R ≘ x × ⁠5/9⁠ K |

## Fahrenheit scale

Temperature conversions :
| | from Fahrenheit | to Fahrenheit |
| Celsius | x °F ≘ (x − 32) × ⁠5/9⁠ °C | x °C ≘ (x × ⁠9/5⁠ + 32) °F |
| Kelvin | x °F ≘ (x + 459.67) × ⁠5/9⁠ K | x K ≘ (x × ⁠9/5⁠ − 459.67) °F |
| Rankine | x °F ≘ (x + 459.67) °R | x °R ≘ (x − 459.67) °F |

## Rankine scale

Temperature conversions :
| | from Rankine | to Rankine |
| Celsius | x °R ≘ (x − 491.67) × ⁠5/9⁠ °C | x °C ≘ (x + 273.15) × ⁠9/5⁠ °R |
| Kelvin | x °R ≘ x × ⁠5/9⁠ K | x K ≘ x × ⁠9/5⁠ °R |
| Fahrenheit | x °R ≘ (x − 459.67) °F | x °F ≘ (x + 459.67) °R |

## Delisle scale

Temperature conversions :
| | from Delisle | to Delisle |
| Celsius | x °De ≘ (100 − x × ⁠2/3⁠) °C | x °C ≘ (100 − x) × ⁠3/2⁠ °De |
| Kelvin | x °De ≘ (373.15 − x × ⁠2/3⁠) K | x K ≘ (373.15 − x) × ⁠3/2⁠ °De |
| Fahrenheit | x °De ≘ (212 − x × ⁠6/5⁠) °F | x °F ≘ (212 − x) × ⁠5/6⁠ °De |
| Rankine | x °De ≘ (671.67 − x × ⁠6/5⁠) °R | x °R ≘ (671.67 − x) × ⁠5/6⁠ °De |

## Newton scale

Temperature conversions :
| | from Newton | to Newton |
| Celsius | x °N ≘ x × ⁠100/33⁠ °C | x °C ≘ x × ⁠33/100⁠ °N |
| Kelvin | x °N ≘ (x × ⁠100/33⁠ + 273.15) K | x K ≘ (x − 273.15) × ⁠33/100⁠ °N |
| Fahrenheit | x °N ≘ (x × ⁠60/11⁠ + 32) °F | x °F ≘ (x − 32) × ⁠11/60⁠ °N |
| Rankine | x °N ≘ (⁠60/11⁠ x + 491.67) °R | x °R ≘ (x − 491.67) × ⁠11/60⁠ °N |

## Réaumur scale

Temperature conversions :
| | from Réaumur | to Réaumur |
| Celsius | x °Ré ≘ x × ⁠5/4⁠ °C | x °C ≘ x × ⁠4/5⁠ °Ré |
| Kelvin | x °Ré ≘ (x × ⁠5/4⁠ + 273.15) K | x K ≘ (x − 273.15) × ⁠4/5⁠ °Ré |
| Fahrenheit | x °Ré ≘ (x × ⁠9/4⁠ + 32) °F | x °F ≘ (x − 32) × ⁠4/9⁠ °Ré |
| Rankine | x °Ré ≘ (x × ⁠9/4⁠ + 491.67) °R | x °R ≘ (x − 491.67) × ⁠4/9⁠ °Ré |

## Rømer scale

Temperature conversions :
| | from Rømer | to Rømer |
| Celsius | x °Rø ≘ (x − 7.5) × ⁠40/21⁠ °C | x °C ≘ (x × ⁠21/40⁠ + 7.5) °Rø |
| Kelvin | x °Rø ≘ ((x − 7.5) × ⁠40/21⁠ + 273.15) K | x K ≘ ((x − 273.15) × ⁠21/40⁠ + 7.5) °Rø |
| Fahrenheit | x °Rø ≘ ((x − 7.5) × ⁠24/7⁠ + 32) °F | x °F ≘ ((x − 32) × ⁠7/24⁠ + 7.5) °Rø |
| Rankine | x °Rø ≘ ((x − 7.5) × ⁠24/7⁠ + 491.67) °R | x °R ≘ ((x − 491.67) × ⁠7/24⁠ + 7.5) °Rø |

## Conversion calculator

Temperature Conversion Calculator :
| Celsius | Fahrenheit | Kelvin | Rankine | Delisle | Newton | Réaumur | Rømer |
| 0 | 32 | 273.15 | 491.67 | 150 | 0 | 0 | 7.5 |

## Comparison values chart

| Celsius | Fahrenheit | Kelvin | Rankine | Delisle | Newton | Réaumur | Rømer |
| 500.00 | 932.00 | 773.15 | 1391.67 | −600.00 | 165.00 | 400.00 | 270.00 |
| 490.00 | 914.00 | 763.15 | 1373.67 | −585.00 | 161.70 | 392.00 | 264.75 |
| 480.00 | 896.00 | 753.15 | 1355.67 | −570.00 | 158.40 | 384.00 | 259.50 |
| 470.00 | 878.00 | 743.15 | 1337.67 | −555.00 | 155.10 | 376.00 | 254.25 |
| 460.00 | 860.00 | 733.15 | 1319.67 | −540.00 | 151.80 | 368.00 | 249.00 |
| 450.00 | 842.00 | 723.15 | 1301.67 | −525.00 | 148.50 | 360.00 | 243.75 |
| 440.00 | 824.00 | 713.15 | 1283.67 | −510.00 | 145.20 | 352.00 | 238.50 |
| 430.00 | 806.00 | 703.15 | 1265.67 | −495.00 | 141.90 | 344.00 | 233.25 |
| 420.00 | 788.00 | 693.15 | 1247.67 | −480.00 | 138.60 | 336.00 | 228.00 |
| 410.00 | 770.00 | 683.15 | 1229.67 | −465.00 | 135.30 | 328.00 | 222.75 |
| 400.00 | 752.00 | 673.15 | 1211.67 | −450.00 | 132.00 | 320.00 | 217.50 |
| 390.00 | 734.00 | 663.15 | 1193.67 | −435.00 | 128.70 | 312.00 | 212.25 |
| 380.00 | 716.00 | 653.15 | 1175.67 | −420.00 | 125.40 | 304.00 | 207.00 |
| 370.00 | 698.00 | 643.15 | 1157.67 | −405.00 | 122.10 | 296.00 | 201.75 |
| 360.00 | 680.00 | 633.15 | 1139.67 | −390.00 | 118.80 | 288.00 | 196.50 |
| 350.00 | 662.00 | 623.15 | 1121.67 | −375.00 | 115.50 | 280.00 | 191.25 |
| 340.00 | 644.00 | 613.15 | 1103.67 | −360.00 | 112.20 | 272.00 | 186.00 |
| 330.00 | 626.00 | 603.15 | 1085.67 | −345.00 | 108.90 | 264.00 | 180.75 |
| 320.00 | 608.00 | 593.15 | 1067.67 | −330.00 | 105.60 | 256.00 | 175.50 |
| 310.00 | 590.00 | 583.15 | 1049.67 | −315.00 | 102.30 | 248.00 | 170.25 |
| 300.00 | 572.00 | 573.15 | 1031.67 | −300.00 | 99.00 | 240.00 | 165.00 |
| 290.00 | 554.00 | 563.15 | 1013.67 | −285.00 | 95.70 | 232.00 | 159.75 |
| 280.00 | 536.00 | 553.15 | 995.67 | −270.00 | 92.40 | 224.00 | 154.50 |
| 270.00 | 518.00 | 543.15 | 977.67 | −255.00 | 89.10 | 216.00 | 149.25 |
| 260.00 | 500.00 | 533.15 | 959.67 | −240.00 | 85.80 | 208.00 | 144.00 |
| 250.00 | 482.00 | 523.15 | 941.67 | −225.00 | 82.50 | 200.00 | 138.75 |
| 240.00 | 464.00 | 513.15 | 923.67 | −210.00 | 79.20 | 192.00 | 133.50 |
| 230.00 | 446.00 | 503.15 | 905.67 | −195.00 | 75.90 | 184.00 | 128.25 |
| 220.00 | 428.00 | 493.15 | 887.67 | −180.00 | 72.60 | 176.00 | 123.00 |
| 210.00 | 410.00 | 483.15 | 869.67 | −165.00 | 69.30 | 168.00 | 117.75 |
| 200.00 | 392.00 | 473.15 | 851.67 | −150.00 | 66.00 | 160.00 | 112.50 |
| 190.00 | 374.00 | 463.15 | 833.67 | −135.00 | 62.70 | 152.00 | 107.25 |
| 180.00 | 356.00 | 453.15 | 815.67 | −120.00 | 59.40 | 144.00 | 102.00 |
| 170.00 | 338.00 | 443.15 | 797.67 | −105.00 | 56.10 | 136.00 | 96.75 |
| 160.00 | 320.00 | 433.15 | 779.67 | −90.00 | 52.80 | 128.00 | 91.50 |
| 150.00 | 302.00 | 423.15 | 761.67 | −75.00 | 49.50 | 120.00 | 86.25 |
| 140.00 | 284.00 | 413.15 | 743.67 | −60.00 | 46.20 | 112.00 | 81.00 |
| 130.00 | 266.00 | 403.15 | 725.67 | −45.00 | 42.90 | 104.00 | 75.75 |
| 120.00 | 248.00 | 393.15 | 707.67 | −30.00 | 39.60 | 96.00 | 70.50 |
| 110.00 | 230.00 | 383.15 | 689.67 | −15.00 | 36.30 | 88.00 | 65.25 |
| 100.00 | 212.00 | 373.15 | 671.67 | 0.00 | 33.00 | 80.00 | 60.00 |
| 90.00 | 194.00 | 363.15 | 653.67 | 15.00 | 29.70 | 72.00 | 54.75 |
| 80.00 | 176.00 | 353.15 | 635.67 | 30.00 | 26.40 | 64.00 | 49.50 |
| 70.00 | 158.00 | 343.15 | 617.67 | 45.00 | 23.10 | 56.00 | 44.25 |
| 60.00 | 140.00 | 333.15 | 599.67 | 60.00 | 19.80 | 48.00 | 39.00 |
| 50.00 | 122.00 | 323.15 | 581.67 | 75.00 | 16.50 | 40.00 | 33.75 |
| 40.00 | 104.00 | 313.15 | 563.67 | 90.00 | 13.20 | 32.00 | 28.50 |
| 30.00 | 86.00 | 303.15 | 545.67 | 105.00 | 9.90 | 24.00 | 23.25 |
| 20.00 | 68.00 | 293.15 | 527.67 | 120.00 | 6.60 | 16.00 | 18.00 |
| 10.00 | 50.00 | 283.15 | 509.67 | 135.00 | 3.30 | 8.00 | 12.75 |
| 0.00 | 32.00 | 273.15 | 491.67 | 150.00 | 0.00 | 0.00 | 7.50 |
| −10.00 | 14.00 | 263.15 | 473.67 | 165.00 | −3.30 | −8.00 | 2.25 |
| −14.26 | 6.29 | 258.86 | 465.96 | 171.43 | −4.71 | −11.43 | 0.00 |
| −17.78 | 0.00 | 255.37 | 459.67 | 176.67 | −5.87 | −14.22 | −1.83 |
| −20.00 | −4.00 | 253.15 | 455.67 | 180.00 | −6.60 | −16.00 | −3.00 |
| −30.00 | −22.00 | 243.15 | 437.67 | 195.00 | −9.90 | −24.00 | −8.25 |
| −40.00 | −40.00 | 233.15 | 419.67 | 210.00 | −13.20 | −32.00 | −13.50 |
| −50.00 | −58.00 | 223.15 | 401.67 | 225.00 | −16.50 | −40.00 | −18.75 |
| −60.00 | −76.00 | 213.15 | 383.67 | 240.00 | −19.80 | −48.00 | −24.00 |
| −70.00 | −94.00 | 203.15 | 365.67 | 255.00 | −23.10 | −56.00 | −29.25 |
| −80.00 | −112.00 | 193.15 | 347.67 | 270.00 | −26.40 | −64.00 | −34.50 |
| −90.00 | −130.00 | 183.15 | 329.67 | 285.00 | −29.70 | −72.00 | −39.75 |
| −100.00 | −148.00 | 173.15 | 311.67 | 300.00 | −33.00 | −80.00 | −45.00 |
| −110.00 | −166.00 | 163.15 | 293.67 | 315.00 | −36.30 | −88.00 | −50.25 |
| −120.00 | −184.00 | 153.15 | 275.67 | 330.00 | −39.60 | −96.00 | −55.50 |
| −130.00 | −202.00 | 143.15 | 257.67 | 345.00 | −42.90 | −104.00 | −60.75 |
| −140.00 | −220.00 | 133.15 | 239.67 | 360.00 | −46.20 | −112.00 | −66.00 |
| −150.00 | −238.00 | 123.15 | 221.67 | 375.00 | −49.50 | −120.00 | −71.25 |
| −160.00 | −256.00 | 113.15 | 203.67 | 390.00 | −52.80 | −128.00 | −76.50 |
| −170.00 | −274.00 | 103.15 | 185.67 | 405.00 | −56.10 | −136.00 | −81.75 |
| −180.00 | −292.00 | 93.15 | 167.67 | 420.00 | −59.40 | −144.00 | −87.00 |
| −190.00 | −310.00 | 83.15 | 149.67 | 435.00 | −62.70 | −152.00 | −92.25 |
| −200.00 | −328.00 | 73.15 | 131.67 | 450.00 | −66.00 | −160.00 | −97.50 |
| −210.00 | −346.00 | 63.15 | 113.67 | 465.00 | −69.30 | −168.00 | −102.75 |
| −220.00 | −364.00 | 53.15 | 95.67 | 480.00 | −72.60 | −176.00 | −108.00 |
| −230.00 | −382.00 | 43.15 | 77.67 | 495.00 | −75.90 | −184.00 | −113.25 |
| −240.00 | −400.00 | 33.15 | 59.67 | 510.00 | −79.20 | −192.00 | −118.50 |
| −250.00 | −418.00 | 23.15 | 41.67 | 525.00 | −82.50 | −200.00 | −123.75 |
| −260.00 | −436.00 | 13.15 | 23.67 | 540.00 | −85.80 | −208.00 | −129.00 |
| −270.00 | −454.00 | 3.15 | 5.67 | 555.00 | −89.10 | −216.00 | −134.25 |
| −273.15 | −459.67 | 0.00 | 0.00 | 559.725 | −90.1395 | −218.52 | −135.90375 |
| Celsius | Fahrenheit | Kelvin | Rankine | Delisle | Newton | Réaumur | Rømer |

## Comparison of temperature scales

Comparison of temperature scales :
| Comment | Kelvin | Celsius | Fahrenheit | Rankine | Delisle | Newton | Réaumur | Rømer |
| Absolute zero | 0.00 | −273.15 | −459.67 | 0.00 | 559.73 | −90.14 | −218.52 | −135.90 |
| Lowest recorded surface temperature on Earth | 184 | −89.2 | −128.6 | 331 | 284 | −29 | −71 | −39 |
| Fahrenheit's ice/salt mixture | 255.37 | −17.78 | 0.00 | 459.67 | 176.67 | −5.87 | −14.22 | −1.83 |
| Ice melts (at standard pressure) | 273.15 | 0.00 | 32.00 | 491.67 | 150.00 | 0.00 | 0.00 | 7.50 |
| Triple point of water | 273.16 | 0.01 | 32.018 | 491.688 | 149.985 | 0.0033 | 0.008 | 7.50525 |
| Average surface temperature on Earth | 288 | 15 | 59 | 519 | 128 | 5 | 12 | 15 |
| Average human body temperature* | 310 | 37 | 98 | 558 | 95 | 12 | 29 | 27 |
| Highest recorded surface temperature on Earth | 331 | 58 | 136.4 | 596 | 63 | 19 | 46 | 38 |
| Water boils (at standard pressure) | 373.1339 | 99.9839 | 211.97102 | 671.64102 | 0.00 | 33.00 | 80.00 | 60.00 |
| Titanium melts | 1941 | 1668 | 3034 | 3494 | −2352 | 550 | 1334 | 883 |
| The surface of the Sun | 5800 | 5500 | 9900 | 10400 | −8100 | 1800 | 4400 | 2900 |
* 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 zero | Lowest recorded surface temperature on Earth | Fahrenheit's ice/water/salt mixture | Melting point of ice (at standard pressure) | Average surface temperature on Earth (15 °C) | Average human body temperature (37 °C) | Highest recorded surface temperature on Earth | Boiling point of water (at standard pressure) | |

## 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}$_K$).