How to Convert Between Fahrenheit, Celsius, and Kelvin

Steps to Convert Celsius to Kelvin

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• Ph.D., Biomedical Sciences, University of Tennessee at Knoxville
• B.A., Physics and Mathematics, Hastings College

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Celsius and Kelvin are the two most important temperature scales for scientific measurements. Fortunately, it’s easy to convert between them because the two scales have the same size degree. All that is needed to convert Celsius to Kelvin is one simple step. (Note it’s “Celsius”, not “Celcius”, a common mis-spelling.)

Celsius to Kelvin Conversion Formula

Take your Celsius temperature and add 273.15.

K = °C + 273.15
Your answer will be in Kelvin.

Remember, the Kelvin temperature scale does not use the degree (°) symbol. The reason is because Kelvin is an absolute scale, based on absolute zero, while the zero on the Celsius scale is based on the properties of water.

Also, measurements given in Kelvin will always be larger numbers than in Celsius.

Celsius to Kelvin Conversion Examples

For example, if you want to know what 20°C is in Kelvin:

K = 20 + 273.15 = 293.15 K

If you want to know what -25.7°C is in Kelvin:

K = -25.7 + 273.15, which may be rewritten as:

K = 273.15 – 25.7 = 247.45 K

More Temperature Conversion Examples

It’s just as easy to convert Kelvin into Celsius. Another important temperature scale is the Fahrenheit scale. If you use this scale, you should be familiar with how to convert Celsius to Fahrenheit and Kelvin to Fahrenheit.

Asked by Wiki User

Wiki User

Answered

December 02, 2010 4:54AM

2010-12-02 04:54:21

It should be the same temperature that you set your hot water heater.

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As we know, in general, there are three kinds of temperature units to record the temperature. And if you want to convert one kind of temperature unit to another, how can you do? Now, this article is introducing the tricks for you to quickly convert temperature units between Celsius, Kelvin and Fahrenheit in Excel.

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Convert temperature units with formula in Excel

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If you have data is recorded as Celsius in Column A and you want the equivalent in Kelvin in Column B:

1. Type this formula in cell B2: =CONVERT(A2,”C”,”K”), see screenshot:

2. Then press Enter button on the keyboard, and drag the fill hand of the B2 to the end of B7, see screenshot:

With the same steps, you also can convert temperature units between Celsius and Fahrenheit, Kelvin and Fahrenheit.

Convert Celsius to Fahrenheit: =CONVERT(A2,”C”,”F”);

Convert Fahrenheit to Celsius: =CONVERT(A2,”F”,”C”);

Convert Kelvin to Fahrenheit: =CONVERT(A2,”K”,”F”);

Convert Fahrenheit to Kelvin: =CONVERT(A2,”F”,”K”).

Convert temperature units with Kutools for Excel

If use formula to convert temperature units is not enough quick and convenient for you, you can try out Kutools for Excel‘s Unit Conversion utility. Unit Conversion is a utility that helps you convert data between multiple units.

Kutools for Excel includes more than 300 handy Excel tools. Free to try with no limitation in 30 days. Get it Now

1. Select the data you want to convert the units.

2. Please apply Kutools for Excel‘s Unit Conversion by clicking Kutools > Content Converter > Unit Conversion. See screenshot:

3. And a Unit Conversion dialog pops up, click the drop-down box and select Temperature under Units option, and then specify the units you want to convert between in the two boxes, you can see the converted result in the Preview. . See screenshot:

4. Click Ok or Apply. All the selected data are converted to the new units. See screenshot:

Note: Applying this utility will change the original data. However, if you want to keep the original data, you can add the converted results as comments by checking the Add results as comments box in the dialog. See screenshot:

With Kutools for Excel‘s Unit Conversions, you can convert multiple units quickly, such as angle units, distance units, time units and so on. Click here to know more about Unit Conversions.

Temperature converter

Celsius To Fahrenheit Just type a value in either box and select the unit of temperature and click on Convert.

Celsius to Fahrenheit formula

°F = °C * 1.8000 + 32.00

0 °C = 32 °F

How do you convert F to C easy?

Quick °C to °F conversion

°C to °F translation is probably the most challenging conversion there is, but a simple °C to °F conversion is quite easy – double the °C figure and add 30. This should be reasonably accurate for weather temperatures.

The Celsius temperature limit was initially defined by placing zero as the temperature at which water froze. Zero degrees C was later redefined as the temperature at which ice flows. The different point at which Celsius was set – 100 degrees Celsius – was established as the boiling point of water.
Since its description, the Celsius scale has been redefined to secure it to Kelvin. Zero degrees Celsius is now described as 273.15K. As one degree Celsius is equivalent to one Kelvin, boiling point of water is equal to 273.15 + 100 = 373.15 Kelvin.

The Fahrenheit temperature limit is based on setting the freezing point of water at 32 degrees and boiling to 212 degrees. This indicates that boiling and freezing point are 180 degrees apart. Absolute zero is set as -459.67°F.

Common conversions from °C to °F

• 25°C= 77°F
• 30°C= 86°F
• 33°C= 91.4°F
• 35°C= 95°F
• 40°C= 104°F
• 180°C= 356°F

Common misspellings of Celsius

• Celcius

Common misspellings of Fahrenheit

• Farenheit
• Farenheight
• Ferenheit
• Ferenheight
• Ferinheit
• Ferinheight
• Fahrinheight
• Fahenhiet

How to convert Celsius to Fahrenheit °C to °F ?

0 degrees Celsius is equal to 32 degrees Fahrenheit:

The temperature T in degrees Fahrenheit (°F) is equal to the temperature T in degrees Celsius (°C) times 9/5 plus 32:

Example

Convert 20 degrees Celsius to degrees Fahrenheit:

Typical Temperatures

16 is about 61
28 is about 82

How do you convert Celsius to Fahrenheit chart? °C to °F Conversion Table

How do you convert Celsius to Fahrenheit?

What does 40 Celsius mean in Fahrenheit?

How do you calculate Farenheit to Celcius?

What is Celsius to Fahrenheit chart?

How do you calculate F to C?

What is 4 degrees Fahrenheit equal to in Celsius?

What temp is 25 degrees Celsius?

What does 45 degrees Fahrenheit equal in Celsius?

Is 45 Fahrenheit hot or cold?

What is the difference between 1 degree Celsius and 1 degree Fahrenheit?

Is 45 degrees Fahrenheit cold?

1 Celsius to Fahrenheit

35° celsius to fahrenheit

what is celsius into fahrenheit

Is 10 degrees C cold?

What should I wear in 46 degree weather?

Is 58 degrees too cold for shorts?

Is 58 degrees warm enough for shorts?

Is 72 degrees warm enough for shorts?

What should a guy wear in 50 degree weather?

You can convert degrees Fahrenheit to degrees Celsius or vice versa by using simple addition, subtraction, multiplication, and division. Next time you’re given the temperature in the wrong scale, you’ll be able to convert it in just a matter of seconds!

Contents

• 1 Steps
  • 1.1 Fahrenheit to Celsius
  • 1.2 Celsius to Fahrenheit
  • 1.3 Celsius to Kelvin
  • 1.4 Kelvin to Celsius
  • 1.5 Kelvin to Fahrenheit
  • 1.6 Fahrenheit to Kelvin
• 2 Video
• 3 Tips
• 4 Related Articles
• 5 Sources and Citations

Steps

Fahrenheit to Celsius

1. Understand the scales. The Fahrenheit and Celsius scales begin at a different number—where 0° Celsius is freezing, that equivalent temperature in Fahrenheit is 32°. In addition to starting at a different temperature, the two scales rise at different rates as well. For instance, the range from freezing to boiling in degrees Celsius is 0-100°, and the same range in degrees Fahrenheit is 32-212°. [1]
2. Subtract 32 from the Fahrenheit temperature. Since freezing for Fahrenheit is 32 and freezing for Celsius is 0, you begin the conversion by subtracting 32 from the Fahrenheit temperature. [1]
   • For example, if your initial Fahrenheit temperature is 74°F, just subtract 32 from 74. 74-32 = 42. [1]
3. Do Division the result by 1.8. The range for freezing to boiling in Celsius is 0-100 whereas it’s 32-212 in Fahrenheit. This is the same as saying that for every 180° Fahrenheit range, there is only a 100° Celsius range. You can express that as 180/100, which when simplified equals 1.8, so to finish the conversion you must divide by 1.8.
   • For the example from step one, divide your result, 42, by 1.8. 42/1.8 = 23°C. Therefore, 74°F can be converted to 23°C.
   • Note that 1.8 is the equivalent of 9/5. If you don’t have a calculator or prefer working with fractions, you can divide your result from the first step by 9/5 instead of 1.8.
4. Check your answer. Here are a few conversions so you can see whether your result makes sense. If you get a result that doesn’t fit this scale, check your math again. You may have forgot to subtract before dividing.Template:Table

Celsius to Fahrenheit

1. Understand the scales. Since the same rules in the scale differences apply when converting Celsius to Fahrenheit as the opposite, you’ll still be using the difference of 32 and the scale difference of 1.8. You just use them in the reverse order.
2. Multiply the Celsius temperature by 1.8. If instead, you want to convert the temperature from degrees Celsius to degrees Fahrenheit, you can simply reverse the process. Begin by multiplying the Celsius temperature by 1.8. [1]
   • For example, if you’re working with the temperature 30°C, you should first multiply it by 1.8, or 9/5. 30 x 1.8 = 54. [1]
3. Add 32 to the result. Now that you have corrected for the differences in scale, you still must correct for the difference in starting points as in step one. To do this, add 32 to the Celsius x 1.8 temperature, and you will have the final temperature in degrees Fahrenheit.
   • Add 32 to 54, which was the result from step 3. 54 + 32 = 86°F. Therefore, 30°C is equivalent to 86°F.
4. Check your answer. If your answer doesn’t fit between two lines of this chart, you’ve probably made a math error. Remember to multiply by 1.8 before adding 32.Template:Table

A more general way to compare the two is to realize that every 5°C equals 9°F:Template:Table Furthermore, given the 1.8 conversion factor, each 1°C difference equals 1.8°F, with that idea highlighted in the 10-15°C range:Template:Table If one rounds the Fahrenheit values, the difference in Fahrenheit from the nearest 5 or 10°C has the pattern 2,4,5,7:Template:Table

Clickable
Temperature
Thermometer

Online Temperature Converter

Understanding Celsius

• 0° – Freezing
• 10° – Cold
• 20° – Room Temperature
• 30° – Hot
• 40° – Sweltering

Temperature Fun Facts

• At high temperatures, degrees Celsius and Kelvins become equal as the difference of 273.15 between them gets lost in the noise.
• -40° Celsius and -40° Fahrenheit are equal.
• Zero Kelvins is absolute zero.
• Body temperature.
• Boiling point of water.
• Freezing point of water.

Temperature Conversion Instructions

Enter a value for any one of the three temperature scales and the others will automatically be calculated. Javascript must be enabled in your web browser for calculations to occur.

Significant figures are used. Results are shown only with as many significant figures as the quantity that was entered. Scientific notation may be used for large results or if the number of significant digits would be ambiguous otherwise. The calculator follows proper rounding rules for scientific purposes.

The formulas used to convert between temperatures are as follows:

• °C = (°F – 32) * 5 / 9
• °F = (°C * 1.8) + 32
• K = °C + 273.15
• °C = K – 273.15

Temperature Converter License

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

About Temperature Conversion

The fahrenheit was proposed by Daniel Gabriel Fahrenheit. The scale is often mispelled as “farhenheit”, “farenheit”, “farhenhiet”, or “farenhiet”.

The Celcius scale is still sometimes called the “centigrade” scale because it is divided into 100 divisions. It was devised by Andres Celsius.

There are not any gas law problems that the ChemTeam is aware of that use the Celsius temperature directly in the calculation.

If you have a Celsius temperature in the problem, you MUST change it to Kelvin, in order to use it in your problem.

Sometimes your teacher might put a temperature in the problem, but you really don’t need to use it. Your teacher is doing what he or she is driven to do: confuse poor teenage kids. The ChemTeam understands this fully for, you see, this is what happened in his class. (The ChemTeam is retired now.) All teachers know this is really fun! OK, back to work.

You can convert between Celsius and Kelvin like this: Kelvin = Celsius + 273.15. Often, the value of 273 is used instead of 273.15. Check with your teacher on this point. All examples to follow will use 273.

A point before going on to some problems: very often in gas law problems it looks like significant figure rules are being violated. The reality is that they are not. In reality, the significant figure concept is more complex than the simple rules taught at this level.

However, having said that, be careful to watch your teacher’s actions in class and ask what the rules are in your class. If I am saying something different than what your teacher wants you to do, please don’t use this phrase (or anything like it) to your teacher: “Well, there’s some guy on the Internet who says you’re wrong.”

Last point: never, ever, use a degree sign on the symbol for Kelvin. Do not do this: °K. This is what is known as an ‘idiot indicator.’ You do that and your study partner will say “Didn’t you learn anything in high school? You’re an idiot.” The ChemTeam will remain silent as to the reasons.

Also, never say ‘degrees Kelvin.’ This value: 225 K is said “two hundred twenty five Kelvins.” Please trust the ChemTeam on these points.

Example #1: Convert 25.0 °C to Kelvin.

Everybody (except you!) in chemistry knows the true conversion value is 273.15, but the decimal portion is usually ignored. Also, the most common type of thermometer in high school labs is readable to the nearest tenth. So temperatures are usually written just to the tenth place at this introductory level

The ChemTeam occasionally had a student who insisted on using 273.15. You may be the same. However, be careful on this. You may do a calculation on a test (or a web-based assignment) using 273.15 and the answer was done with 273. That difference may generate a value for your answer that causes a deduction of points. Follow the policy your classroom teacher sets down.

Sometimes a teacher will have you use 273.0. The ChemTeam tended not to do that during his teaching career; you should make sure to follow your teacher’s lead.

Example #2: Convert 375 K to degrees Celsius.

Notice how I tend to leave off the units in the problem and only use the unit on the final answer.

Example #3: Convert −50 °C to Kelvin.

More temperature conversion examples:

1) What temperature scale must always be used when working gas law problems? Ans: Kelvin

2) The boiling point of water on the Kelvin scale is _____. Ans: 373 K.

3) 0 K is also known as ________. Ans: absolute zero.

4) 40.0 °C is what temperature on the Kelvin scale? Ans: 313 K

5) −20.0 °C is what temperature on the Kelvin scale? Ans: 253 K

6) 298 K is what temperature in degrees Celsius? Ans: 25 °C

7) What is the temperature (give in both °C and K) at STP? Ans: 0 °C and 273 K

8) The freezing point of water on the Kelvin scale is _____. Ans: 273 K.

9) Convert −145.0 °C to K. Ans: 128 K

10) Convert 252 K to °C. Ans: −21 °C

11) Is it possible to have a negative Kelvin temperature? Ans: no.

Quick Celsius (°C) / Fahrenheit (°F) Conversion:

Just type a value in either box:

Typical Temperatures

16 is about 61
28 is about 82

Explanation

There are two main temperature scales:

They both measure the same thing (temperature!), but use different numbers:

• Boiling water (at normal pressure) measures 100° in Celsius, but 212° in Fahrenheit
• And as water freezes it measures 0° in Celsius, but 32° in Fahrenheit

Looking at the diagram, notice:

• The scales start at a different number (0 vs 32), so we will need to add or subtract 32
• The scales rise at a different rate (100 vs 180), so we will also need to multiply

And so, to convert:

180100 can be simplified to 95 , and 100180 can be simplified to 59 , so this is the easiest way:

°C to °F: Divide by 5, then multiply by 9, then add 32

°F to °C: Subtract 32, then multiply by 5, then divide by 9

Example: Convert 25° Celsius (a nice warm day) to Fahrenheit

First: 25° / 5 = 5
Then: 5 × 9 = 45
Then: 45 + 32 = 77° F

Example: Convert 98.6° Fahrenheit (normal body temperature) to Celsius

First: 98.6° − 32 = 66.6
Then: 66.6 × 5 = 333
Then: 333 / 9 = 37° C

We can swap the order of divide and multiply if we want, but don’t change the add or subtract. So this is also OK:

Example: Convert 98.6° Fahrenheit to Celsius (again)

First: 98.6° − 32 = 66.6
Then: 66.6 / 9 = 7.4
Then: 7.4 × 5 = 37° C

(Same answer as before, was it easier or harder this way?)

We can write each as a formula like this:

Other Methods That Work

Use 1.8 instead of 9/5

9/5 is equal to 1.8, so we can also use this method:

To make “×1.8” easier we can multiply by 2 and subtract 10%, but it only works for °C to °F:

Example: Convert 20° Celsius (A nice day) to Fahrenheit

• 20x2 = 40
• less 10% is 40−4 = 36
• 36+32 = 68° F

Add 40, Multiply, Subtract 40

Since both scales cross at −40° (−40° C equals −40° F) we can:

• add 40,
• multiply by 5/9 (for °F to °C), or 9/5 (for °C to °F)
• subtract 40

Example: Convert 10° Celsius (A cool day) to Fahrenheit

• 10+40 = 50
• 50×9/5 = 90
• 90−40 = 50° F

To remember 9/5 for °C to °F think “F is greater than C, so there are more °F than °C”

Quick, but Not Accurate

• 0° C → 0+30 → 30° F (low by 2°)
• 10° C → 20+30 → 50° F (exact!)
• 30° C → 60+30 → 90° F (high by 4°)
• 180° C → 360+30 → 390° F (high by 34°, not good)

• 40° F → 10/2 → 5° C (almost right )
• 80° F → 50/2 → 25° C (low by about 2°)
• 120° F → 90/2 → 45° C (low by about 4°)
• 450° F → 420/2 → 210° C (low by about 22°, not good)

Footnote: Temperature is a measure of how fast an objects particles are moving.

• To identify the different between temperature and heat
• To recognize the different scales used to measuring temperature

The concept of temperature may seem familiar to you, but many people confuse temperature with heat. Temperature is a measure of how hot or cold an object is relative to another object (its thermal energy content), whereas heat is the flow of thermal energy between objects with different temperatures.

Three different scales are commonly used to measure temperature: Fahrenheit (expressed as °F), Celsius (°C), and Kelvin (K). Thermometers measure temperature by using materials that expand or contract when heated or cooled. Mercury or alcohol thermometers, for example, have a reservoir of liquid that expands when heated and contracts when cooled, so the liquid column lengthens or shortens as the temperature of the liquid changes.

The Fahrenheit Scale

The Fahrenheit temperature scale was developed in 1717 by the German physicist Gabriel Fahrenheit, who designated the temperature of a bath of ice melting in a solution of salt as the zero point on his scale. Such a solution was commonly used in the 18th century to carry out low-temperature reactions in the laboratory. The scale was measured in increments of 12; its upper end, designated as 96°, was based on the armpit temperature of a healthy person—in this case, Fahrenheit’s wife. Later, the number of increments shown on a thermometer increased as measurements became more precise. The upper point is based on the boiling point of water, designated as 212° to maintain the original magnitude of a Fahrenheit degree, whereas the melting point of ice is designated as 32°.

The Celsius Scale

The Celsius scale was developed in 1742 by the Swedish astronomer Anders Celsius. It is based on the melting and boiling points of water under normal atmospheric conditions. The current scale is an inverted form of the original scale, which was divided into 100 increments. Because of these 100 divisions, the Celsius scale is also called the centigrade scale.

The Kelvin Scale

Lord Kelvin, working in Scotland, developed the Kelvin scale in 1848. His scale uses molecular energy to define the extremes of hot and cold. Absolute zero, or 0 K, corresponds to the point at which molecular energy is at a minimum. The Kelvin scale is preferred in scientific work, although the Celsius scale is also commonly used. Temperatures measured on the Kelvin scale are reported simply as K, not °K.

Figure(PageIndex): A Comparison of the Fahrenheit, Celsius, and Kelvin Temperature Scales. Because the difference between the freezing point of water and the boiling point of water is 100° on both the Celsius and Kelvin scales, the size of a degree Celsius (°C) and a kelvin (K) are precisely the same. In contrast, both a degree Celsius and a kelvin are 9/5 the size of a degree Fahrenheit (°F).

Converting between Scales

The kelvin is the same size as the Celsius degree, so measurements are easily converted from one to the other. The freezing point of water is 0°C = 273.15 K; the boiling point of water is 100°C = 373.15 K. The Kelvin and Celsius scales are related as follows:

T (in °C) + 273.15 = T (in K)

T (in K) − 273.15 = T (in °C)

Degrees on the Fahrenheit scale, however, are based on an English tradition of using 12 divisions, just as 1 ft = 12 in. The relationship between degrees Fahrenheit and degrees Celsius is as follows:where the coefficient for degrees Fahrenheit is exact. (Some calculators have a function that allows you to convert directly between °F and °C.) There is only one temperature for which the numerical value is the same on both the Fahrenheit and Celsius scales: −40°C = −40°F. The relationship between the scales are as follows:

Convert the temperature of the surface of the sun (5800 K) and the boiling points of gold (3080 K) and liquid nitrogen (77.36 K) to °C and °F.A student is ill with a temperature of 103.5°F. What is her temperature in °C and K?

Converting between temperatures on the Celsius and Fahrenheit scales is easy. I’ve been doing it in my head for over a decade now. Yeah, I know I’m a weirdo, using the metric system here in the US when no one else does. But if you’ve been reading this blog for a while, you already knew I was odd, especially if you’ve also read my bio over at Green Building Advisor.

Anyway, it’s helpful to be able to convert between Celsius and Fahrenheit if you go to other some other countries. Well, OK, it’s pretty much all other countries. You could, of course, install an app on your phone that would do the conversion for you, but where’s the fun in that?!

Imagine that you woke up today in Atlanta, and all the news outlets were suddenly talking only in Celsius temperatures. Their forecast for the whole upcoming weekend, Friday through Sunday, is for a high temperature of 39° C.

Is that really hot? Is it going to be a gorgeous weekend? Should you make sure your furnace is working? Buy ice?

You could try to remember that equation you learned in school. Let’s see, do I add 32 and then multiply by 1.8? Do I divide by 1.8 and subtract 32? What order do I do that in, and which one is which? Where’s my calculator?!

That’s the hard way, my friend! The easy way is to learn the principles in the table below.

Notice the two lines highlighted in yellow. Those are my two main reference points. I can figure out any temperature I want by skipping along in 5° C increments, each time adding or subtracting 9° F. When a temperature is between the numbers in the table, then I look at which line it’s closest to and add or subtract multiples of 1.8° F for each degree C.

It’s really not that hard. And yes, 39° C really is the forecast for Atlanta this weekend. You should be able to figure out from the table above that that is going to have us living up to our silly nickname: Hotlanta!

What’s the difference between Celsius and Fahrenheit? It’s really a quirk of history and a simple mathematical conversion. Learn the easiest way to convert Fahrenheit to Celsius as well as the reverse calculation with simple equations and a chart.

Converting Fahrenheit to Celsius

Some would consider a quick estimate the easiest way to convert a Fahrenheit temperature to a Celsius temperature. Others want a more precise answer quickly. Here, you can learn both methods.

Fahrenheit to Celsius Estimate Formula

Use this formula to get a good estimate of the Celsius temperature when converting from Fahrenheit. In this case / means divided by or to use division.

(Fahrenheit temp. [F]-30)/2 = Celsius temp.

In other words, if you’d like to convert a Fahrenheit temperature to an approximate Celsius temperature:

1. Start with the temperature in Fahrenheit (e.g., 100 degrees).
2. Subtract 30 from this figure (e.g., 100 – 30 = 70).
3. Divide your answer by 2 (e.g., 70 / 2 = 35).

Fahrenheit to Celsius Exact Formula

If you want a more precise calculation, you can use the more exact formula. Using this calculation, we determine that 100 degrees Fahrenheit is equivalent to 37.78 degrees Celsius.

In other words, if you’d like to convert a temperature reading in Fahrenheit to Celsius:

1. Start with the temperature in Fahrenheit (e.g., 100 degrees).
2. Subtract 32 from this figure (e.g., 100 – 32 = 68).
3. Divide your answer by 1.8 (e.g., 68 / 1.8 = 37.78)

Converting Celsius to Fahrenheit

To convert Celsius to Fahrenheit, simply reverse the equation. In this case * means times, or to use multiplication.

You can use this equation to show that 100 degrees Celsius is equal to 212 degrees Fahrenheit.

1. Start with the temperature in Celsius (e.g., 100 degrees).
2. Multiply this figure by 1.8 (e.g., 100 * 1.8 = 180).
3. Add 32 to this figure (e.g., 180 + 32 = 212).

Fahrenheit to Celsius Conversion Chart

If you really want an easy way to convert temperatures, you can use this Fahrenheit to Celsius conversion chart where the math has already been done for you.

What’s the Difference Between Fahrenheit and Celsius?

If you’re from the United States, you’re probably accustomed to describing temperature by Fahrenheit. A very hot summer day is 100 degrees, a pleasant spring morning is 50 degrees, and 0 degrees is ungodly cold. If you’re from almost anywhere else, you likely favor Celsius, where 0 degrees is only pretty cold, 50 degrees is unspeakably hot, and 100 degrees happens on a stove, not outside.

Are Fahrenheit and Celsius Readings Ever the Same?

If you were wondering if there is a temperature where Fahrenheit and Celsius are the same, it’s at 40 below zero, also known as -40 or negative 40. At all other temperatures, the difference is history.

History of Fahrenheit and Celsius Scales

Globally, the standard scale for everyday use is Celsius. Only the United States, islands freely associated with the US (Palau, the Marshall Islands and Micronesia), the Bahamas, the Caymans, and Liberia use Fahrenheit as their primary temperature measurement. Everybody else goes with Celsius.

History of the Fahrenheit Scale

The Fahrenheit scale was created by Daniel Gabriel Fahrenheit in 1724. Fahrenheit invented his scale for use with mercury thermometers, which he also invented. The Fahrenheit scale is a bit older than the Celsius scale.

History of the Celsius Scale

The Celsius scale was created by Anders Celsius in 1745, a couple decades after Fahrenheit. Curiously, Celsius created the reverse of the modern scale, treating 0 as the boiling point of water and 100 as the freezing point of water. Other scientists, notably Carl Linnaeus, flipped it later that year, making 0 the freezing point and 100 the boiling point of water.

Since it was originally built as a scale between 0 and 100, Celsius is also called centigrade. The word “centigrade” literally describes something that consists of or is divided into 100 degrees. That said, Celsius has been the preferred nomenclature since 1948.

The Kelvin Temperature Unit

You may have heard of temperature being measured according to kelvin. Indeed, if you’re involved in the sciences, you probably use kelvin. Kelvin is a bit different than Fahrenheit and Celsius. Celsius and Fahrenheit are both temperature scales, measuring temperatures in degrees.

History of the Kelvin Unit

Named after Lord Kelvin, a kelvin is a standard scientific unit, like a kilogram for weight or a meter for distance. The proper way to use the word, then, is not “100 degrees Kelvin” but “100 kelvin.” (Note the lower case “k” in kelvin.)

1 kelvin equals 1/273.16th of the triple point of water: that is, the point at which liquid water, water vapor and solid ice can coexist. In other words, 273.16 kelvin is the exact triple point of water.

The Importance of Kelvin

The importance of kelvin is that it measures absolute temperature: absolute zero is 0 kelvin, the temperature at which all atomic motion (which creates heat) stops. There is no thermal energy whatsoever at absolute zero.

Kelvin Conversion Formulas

Kelvin is primarily of value to scientists, since it simplifies calculation at extreme temperatures. For your convenience, the conversion equations follow.

To convert: Celsius to kelvin: C + 273.15 = K.

To convert Fahrenheit to kelvin: [(F – 32) / 1.8] + 273.15 = K

You convert Celsius to Kelvin by simply adding 273.15. If the outside temperature is 10 degrees Celsius, then it is 283.15 kelvin. That’s easy enough.

Fahrenheit is a bit trickier. Take your degrees Fahrenheit, subtract 32, divide by 1.8, and finally add 273.15. Here’s a quick example:

1. Say it is 100 degrees Fahrenheit outside.
2. Subtract 32 from 100 to get 68.
3. Divide 68 by 1.8 to get 37.78.
4. Add 273.15 to get 310.93. Thus, 100 degrees Fahrenheit is equal to 310.93 kelvin.

Taking Temperatures

Temperature is important! Measuring heat accurately matters in every field of human endeavor, from engineering to medicine. For more on how to manage your temperature, take a look at this automatic Celsius to Fahrenheit converter. It’ll make short work of all your temperature conversions.