Physics calculators

Fahrenheit To Celsius Calculator

Updated Jul 7, 2026 By Jehan Wadia
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Converting Fahrenheit (°F) to Celsius (°C)

0.00°C

32°F is equal to 0.00°C

Step-by-Step Solution
Conversion Relationship
Common Temperature Reference Points
Description °F °C
Absolute Zero −459.67°F−273.15°C
Water Freezes 32°F0.00°C
Room Temperature 72°F22.22°C
Human Body Temp 98.6°F37.00°C
Water Boils 212°F100.00°C

Introduction

This Fahrenheit to Celsius calculator lets you convert temperatures between °F and °C in seconds. Just type in a number, and the tool does the math for you. It shows the answer right away, along with a step-by-step breakdown of how the conversion works.

Fahrenheit and Celsius are two scales used to measure temperature. The United States mainly uses Fahrenheit, while most other countries use Celsius. The formula to convert Fahrenheit to Celsius is simple: subtract 32 from the Fahrenheit value, then divide by 1.8. For example, 32°F equals 0°C, which is the point where water freezes.

You can also swap the direction and convert Celsius to Fahrenheit with one click. The calculator includes a chart that plots the conversion line, a reference table of common temperatures, and clear steps so you can follow the math on your own. Whether you need it for school, travel, cooking, or science, this tool gives you a fast and accurate answer every time.

How to Use Our Fahrenheit to Celsius Calculator

Type a temperature value and this calculator will convert it for you. It shows the answer, the math steps, a chart, and a reference table.

Enter a temperature: Type the number you want to convert into the input field on the left. The calculator starts in Fahrenheit (°F) by default.

Change the sign: Click the ± button to switch your number between positive and negative. Use this for below-zero temperatures.

Swap the direction: Click the swap button in the middle to switch between Fahrenheit to Celsius and Celsius to Fahrenheit.

Get your result: Click the Calculate button to see the converted temperature. The answer appears on the right and in the result box below.

Start over: Click the Reset button to clear your work and go back to the default value of 32°F.

How to Convert Fahrenheit to Celsius

Fahrenheit and Celsius are two scales used to measure temperature. Fahrenheit (°F) is mostly used in the United States. Celsius (°C) is used in most other countries around the world. Both scales tell you how hot or cold something is, but they use different numbers to do it.

The Conversion Formula

To change Fahrenheit to Celsius, subtract 32 from the Fahrenheit number, then divide by 1.8. The formula looks like this:

°C = (°F − 32) ÷ 1.8

To go the other way and change Celsius to Fahrenheit, multiply the Celsius number by 1.8, then add 32:

°F = (°C × 1.8) + 32

Key Temperatures to Know

Some temperatures are helpful to remember. Water freezes at 32°F, which is 0°C. Water boils at 212°F, which is 100°C. Normal human body temperature is about 98.6°F, or 37°C. Room temperature is around 72°F, or about 22°C.

Why Two Scales Exist

Daniel Gabriel Fahrenheit created the Fahrenheit scale in 1724. He based it on three fixed points, including the temperature of a salt and ice mixture. Anders Celsius created the Celsius scale in 1742. He based it on water — 0 for freezing and 100 for boiling. Because the Celsius scale ties directly to water, most scientists and most countries prefer it. The Celsius scale is also part of the metric system, which is why it pairs well with tools like the meters to feet calculator when working across measurement systems.

When You Need to Convert

You may need to convert temperatures when you travel, cook with a recipe from another country, or read weather reports from places that use a different scale. Temperature conversions also come up when calculating values like the heat index, the wind chill, or the dew point, since these formulas often require consistent units. In science and engineering, accurate temperature values are essential for calculations involving thermal expansion or the ideal gas law. This calculator does the math for you instantly and shows each step so you can learn how it works.


Formulas used

Fahrenheit to Celsius
{}^{\circ}\mathrm{C} = \dfrac{{}^{\circ}\mathrm{F} - 32}{1.8}
Celsius to Fahrenheit
{}^{\circ}\mathrm{F} = ({}^{\circ}\mathrm{C} \times 1.8) + 32

Frequently asked questions

What is the formula to convert Fahrenheit to Celsius?

The formula is °C = (°F − 32) ÷ 1.8. You subtract 32 from the Fahrenheit value, then divide the result by 1.8. For example, 68°F minus 32 is 36, and 36 divided by 1.8 is 20°C.

What is 100°F in Celsius?

100°F is equal to 37.78°C. This is just above normal human body temperature, which is 98.6°F or 37°C.

What is 0°F in Celsius?

0°F is equal to −17.78°C. This is a very cold temperature, well below the freezing point of water.

At what temperature are Fahrenheit and Celsius the same?

Fahrenheit and Celsius are the same at −40 degrees. That means −40°F = −40°C. This is the only point where both scales meet.

Can this calculator convert negative temperatures?

Yes. You can type a negative number directly into the input field, or click the ± button to flip your number from positive to negative. The calculator handles all temperatures, including values below zero.

How accurate is this Fahrenheit to Celsius calculator?

The calculator gives results rounded to two decimal places. It uses the exact conversion formula, so the answer is as accurate as the standard math allows.

Why does the formula use 1.8 instead of 9/5?

The numbers 1.8 and 9/5 are the same thing. 9 divided by 5 equals 1.8. Some people prefer the fraction, while others find the decimal easier to work with. Both give the same answer.

What does the chart on the calculator show?

The chart draws a straight line that shows how Fahrenheit and Celsius relate to each other. An orange dot marks your specific input value on the line, so you can see where your temperature falls.

Why is 32°F the default value in the calculator?

32°F is the freezing point of water, which equals 0°C. It is one of the most well-known reference points in temperature conversion, so it makes a good starting example.

How do I convert a fever temperature from Fahrenheit to Celsius?

Type the fever reading into the calculator. For example, a fever of 101°F equals 38.33°C. In most countries that use Celsius, a temperature above 38°C is considered a fever.

What is the difference between Fahrenheit and Celsius degree sizes?

A Celsius degree is bigger than a Fahrenheit degree. One degree Celsius equals 1.8 degrees Fahrenheit. This is why the Celsius scale uses smaller numbers for the same temperature.

How do I convert oven temperatures from Fahrenheit to Celsius?

Enter the oven temperature into the calculator. Common examples: 350°F = 176.67°C, 400°F = 204.44°C, and 450°F = 232.22°C. Many recipes from the US list oven temps in Fahrenheit.

Does this tool work on phones and tablets?

Yes. The calculator is designed to work on all screen sizes, including phones, tablets, and desktop computers. All buttons and fields adjust to fit your screen.

What does the reference table at the bottom do?

The table shows five common temperatures like water freezing, water boiling, and body temperature. It highlights the row that is closest to your input value, so you can quickly see where your temperature sits among familiar benchmarks.

Can I use this calculator for science homework?

Yes. The calculator shows a step-by-step solution with the formula, substitution, and final answer. You can follow the same steps in your homework to show your work.