Temperature Converter: Celsius, Fahrenheit, Kelvin

By HesaplayıcıUpdated: September 13, 2026

The temperature converter converts a temperature between Celsius (°C), Fahrenheit (°F) and Kelvin (K). Enter the value and choose the scale to convert from and the scale to convert to. You get the result and the temperature in all three scales, with the formula of each step. Values below absolute zero, 0 K, are rejected.

Worked example: 37 °C in Fahrenheit

Result

98.6 °F

In other units

Celsius: 37 °C
Kelvin: 310.15 K

Step by step

Result
°F = °C × 9/5 + 32
°F = 37 × 9/5 + 32 = 98.6 °F
Kelvin
K = °C + 273.15
K = 37 + 273.15 = 310.15 K

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How to use

Enter the Temperature you want to convert. It can be negative.
In From, choose the scale of the value.
In To, choose the scale of the result and press Calculate.

Formula

°F = °C × 9/5 + 32
°C = (°F − 32) × 5/9
K = °C + 273.15
°C = K − 273.15
K = (°F + 459.67) × 5/9
°F = K × 9/5 − 459.67

°C, °F and K are the temperature in degrees Celsius, degrees Fahrenheit and kelvins. The factor 9/5, or 1.8, comes from one Celsius degree being 1.8 Fahrenheit degrees. The kelvin and the Celsius degree are the same size; the two scales differ only by 273.15.

Worked example

The worked example on this page converts 37 °C, body temperature, to Fahrenheit. The steps give the formula of the target scale and the same temperature in kelvins.

Limits

The converter converts a temperature, not a difference between two temperatures. The Rankine and Réaumur scales are not included. Values below absolute zero are rejected. Results are rounded to 12 significant digits, which only removes tiny floating-point errors.

Frequently Asked Questions

How do you convert Celsius to Fahrenheit?

Multiply the Celsius value by 1.8 and add 32. For example, water boils at 100 °C, which is 212 °F.

How do you convert Kelvin to Celsius?

Subtract 273.15 from the kelvin value. For example, 0 °C is 273.15 K.

What is absolute zero?

Absolute zero is 0 K, which is −273.15 °C and −459.67 °F. No temperature is lower.

How do you convert a temperature difference?

For a difference, no constant is added: a difference of 1 °C is 1 K and 1.8 °F. This converter converts temperatures, not differences.

Calculation rules

Definitions: T(K) = t(°C) + 273.15 and t(°F) = 1.8 × t(°C) + 32 (BIPM SI Brochure; NIST SP 811).

Absolute zero is 0 K = −273.15 °C = −459.67 °F; values below it are rejected.

The converter converts a temperature, not a difference between two temperatures. For a difference, 1 °C = 1 K = 1.8 °F.

Results are rounded to 12 significant digits, which only removes tiny floating-point errors.