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
Kelvin scale
Fahrenheit scale
Rankine scale
Delisle scale
Newton scale
Réaumur scale
Rømer scale
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
| 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[1] | −128.6[1] | 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[2] | 136.4[2] | 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.
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[1] | 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[2] | Boiling point of water (at standard pressure) | |||
Conversion table between the different temperature units
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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 Fahrenheit to Celsius, the formula is {ΔT}°F = 9/5{ΔT}°C.
To convert a delta temperature from Celsius to Kelvin, it is 1:1 ({ΔT}°C = {ΔT}K).
See also
Notes and references
- ↑ 1.0 1.1 1.2 1.3 The Coldest Inhabited Places on Earth; researchers of the Vostok Station recorded the coldest known temperature on Earth on July 21st 1983: −89.2 °C (−128.6 °F).
- ↑ 2.0 2.1 2.2 2.3 "World: Highest Temperature". November 12, 2007. Archived from the original on January 4, 2013. https://web.archive.org/web/20130104143844/http://wmo.asu.edu/world-highest-temperature. "an Italian weather station in al 'Aziziyah (Libya) measured a temperature of 58 °C (136.4 °F) on September 13th 1922. "Although this record has gained general acceptance as the world's highest temperature recorded under standard conditions, the validity of the extreme has been questioned.""
- ↑ Wong, Lena (1997). "Temperature of a healthy human (body temperature)". in Elert, Glenn. https://hypertextbook.com/facts/1997/LenaWong.shtml. Retrieved 2018-06-07.
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