Temperature Converter

Convert between Celsius, Fahrenheit, Kelvin and Rankine instantly. Enter a value, pick your units, and see every conversion at once — plus the formula used for each calculation.

Convert temperature

Enter a value and select units to convert between all temperature scales instantly.

Conversion result

Enter a value and tap Convert

Celsius
°C
Fahrenheit
°F
Kelvin
K
Rankine
°R

About the Temperature Converter

Temperature is one of the most fundamental physical quantities, and different scales are used across science, engineering, and everyday life. Our temperature converter lets you switch between Celsius (used worldwide), Fahrenheit (common in the US), Kelvin (the SI base unit for thermodynamic temperature), and Rankine (used in some engineering contexts) — all in real time.

How the formulas work

Each conversion uses a well-known formula. For example, °F = °C × 9/5 + 32 and K = °C + 273.15. The converter first normalises your input to Celsius, then derives every other scale from that base. The formula used for your selected conversion is displayed alongside the result so you can verify or learn the maths.

Common conversions

Water freezes at 0 °C / 32 °F / 273.15 K and boils at 100 °C / 212 °F / 373.15 K. Absolute zero — the lowest theoretically possible temperature — is −273.15 °C / 0 K / 0 °R. All calculations run entirely in your browser with no data sent to any server.

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