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, and thus temperatures on different scales are more correctly described as corresponding.

Fahrenheit scale

Réaumur 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

* 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 precision.
Some numbers in this table have been rounded.

Graphical representation

Converting units of temperature differences

Converting units of temperature differences 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