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Temperature Converter

Convert between Celsius, Fahrenheit and Kelvin in real time using the standard scale relationships, with a guard against values below absolute zero.

TOOLMERA / CONVERTERS
Temperature Converter
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Converted value33.8
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WHY TOOLMERA

Built to get the task done.

  • 3 temperature scales
  • Formula-accurate conversion
  • Absolute-zero validation
ABOUT THIS TOOL

Temperature Converter — Celsius, Fahrenheit & Kelvin

Convert Celsius, Fahrenheit and Kelvin instantly with standard formulas, quick reference values and absolute-zero validation.

Temperature conversion formulas

Celsius, Fahrenheit and Kelvin use different zero points and scale relationships. Toolmera converts the input to Celsius first, then calculates the requested output scale.

The calculator rejects inputs that would represent a temperature below absolute zero.

Celsius → Fahrenheit°F = (°C × 9/5) + 32
Fahrenheit → Celsius°C = (°F − 32) × 5/9
Celsius → KelvinK = °C + 273.15
Kelvin → Celsius°C = K − 273.15

Useful temperature reference points

Reference values make it easier to sanity-check a conversion. Water freezes at 0 °C / 32 °F under standard reference conditions, while −40 is the point where Celsius and Fahrenheit have the same numeric value.

Kelvin starts at absolute zero, so negative Kelvin values are not physically valid in this converter.

Absolute zero0 K = −273.15 °C = −459.67 °F
Water freezing point0 °C = 32 °F = 273.15 K
−40 point−40 °C = −40 °F
Water boiling point100 °C = 212 °F = 373.15 K
HOW IT WORKS

How to use Temperature Converter

01

Enter a measurement

Type the value and select the source unit.

02

Choose the target unit

Select the unit you want to convert into or use a quick pair.

03

Read the conversion

The result and available comparison values update immediately.

NEXT STEP

Continue your workflow

convert metric and imperial length units
KEEP GOING

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FAQ

Common questions

At what temperature are Celsius and Fahrenheit equal?

They are equal at −40: −40 °C is exactly −40 °F.

Can I enter a temperature below absolute zero?

No. Toolmera flags any input that converts to less than 0 K, which is below absolute zero.

How do I convert Celsius to Fahrenheit?

Multiply Celsius by 9/5 and add 32.

How do I convert Celsius to Kelvin?

Add 273.15 to the Celsius value.