Conversion table between the different temperature units
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 ]
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 [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.
| 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) | |||
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).
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."
Absolute zero is the lowest limit of the thermodynamic temperature scale; a state at which the enthalpy and entropy of a cooled ideal gas reach their minimum value. The fundamental particles of nature have minimum vibrational motion, retaining only quantum mechanical, zero-point energy-induced particle motion. The theoretical temperature is determined by extrapolating the ideal gas law; by international agreement, absolute zero is taken as 0 kelvin, which is −273.15 degrees on the Celsius scale, and equals −459.67 degrees on the Fahrenheit scale. The Kelvin and Rankine temperature scales set their zero points at absolute zero by definition.
Conversion of units is the conversion of the unit of measurement in which a quantity is expressed, typically through a multiplicative conversion factor that changes the unit without changing the quantity. This is also often loosely taken to include replacement of a quantity with a corresponding quantity that describes the same physical property.
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Thermodynamic temperature is a quantity defined in thermodynamics as distinct from kinetic theory or statistical mechanics.
A calorimeter is a device used for calorimetry, or the process of measuring the heat of chemical reactions or physical changes as well as heat capacity. Differential scanning calorimeters, isothermal micro calorimeters, titration calorimeters and accelerated rate calorimeters are among the most common types. A simple calorimeter just consists of a thermometer attached to a metal container full of water suspended above a combustion chamber. It is one of the measurement devices used in the study of thermodynamics, chemistry, and biochemistry.
The Prandtl number (Pr) or Prandtl group is a dimensionless number, named after the German physicist Ludwig Prandtl, defined as the ratio of momentum diffusivity to thermal diffusivity. The Prandtl number is given as:
In chemistry, the molar mass of a chemical compound is defined as the ratio between the mass and the amount of substance of any sample of the compound. The molar mass is a bulk, not molecular, property of a substance. The molar mass is an average of many instances of the compound, which often vary in mass due to the presence of isotopes. Most commonly, the molar mass is computed from the standard atomic weights and is thus a terrestrial average and a function of the relative abundance of the isotopes of the constituent atoms on Earth. The molar mass is appropriate for converting between the mass of a substance and the amount of a substance for bulk quantities.
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In probability theory and statistics, the coefficient of variation (CV), also known as normalized root-mean-square deviation (NRMSD), percent RMS, and relative standard deviation (RSD), is a standardized measure of dispersion of a probability distribution or frequency distribution. It is defined as the ratio of the standard deviation to the mean , and often expressed as a percentage ("%RSD"). The CV or RSD is widely used in analytical chemistry to express the precision and repeatability of an assay. It is also commonly used in fields such as engineering or physics when doing quality assurance studies and ANOVA gauge R&R, by economists and investors in economic models, and in psychology/neuroscience.
The term degree is used in several scales of temperature, with the notable exception of kelvin, primary unit of temperature for engineering and the physical sciences. The degree symbol ° is usually used, followed by the initial letter of the unit; for example, "°C" for degree Celsius. A degree can be defined as a set change in temperature measured against a given scale; for example, one degree Celsius is one-hundredth of the temperature change between the point at which water starts to change state from solid to liquid state and the point at which it starts to change from its liquid to gaseous state.
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The degree Celsius is the unit of temperature on the Celsius temperature scale, one of two temperature scales used in the International System of Units (SI), the other being the closely related Kelvin scale. The degree Celsius can refer to a specific point on the Celsius temperature scale or to a difference or range between two temperatures. It is named after the Swedish astronomer Anders Celsius (1701–1744), who proposed the first version of it in 1742. The unit was called centigrade in several languages for many years. In 1948, the International Committee for Weights and Measures renamed it to honor Celsius and also to remove confusion with the term for one hundredth of a gradian in some languages. Most countries use this scale.
The kelvin is the base unit for temperature in the International System of Units (SI). The Kelvin scale is an absolute temperature scale that starts at the lowest possible temperature, taken to be 0 K. By definition, the Celsius scale and the Kelvin scale have the exact same magnitude; that is, a rise of 1 K is equal to a rise of 1 °C and vice versa, and any temperature in degrees Celsius can be converted to kelvin by adding 273.15.
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