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 | 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 |
| 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[1] | 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[2] | 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.[3]
Some numbers in this table have been rounded.
File:Comparison of temperature scales blank.svg | 845x580px | circle 40 330 4 0 K / 0 °R (−273.15 °C)circle 504 330 4 0 °F (−17.78 °C)circle 537 270 4 150 °Dcircle 537 317 4 32 °Fcircle 537 325 4 7.5 °Røcircle 537 332 4 0 °C / 0 °Ré / 0 °Ncircle 718 245 4 212 °Fcircle 718 290 4 100 °Ccircle 718 298 4 80 °Récircle 718 306 4 60 °Røcircle 718 317 4 33 °Ncircle 718 330 4 0 °Drect 0 0 845 580 desc none | 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 (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
To convert a delta temperature from degrees Celsius to kelvin, it is 1:1