Temperature Converter

Convert between Celsius, Fahrenheit, Kelvin, and Rankine temperature scales. View the conversion formula for each result.

About this Calculator

Convert between Celsius, Fahrenheit, Kelvin, and Rankine temperature scales. View the conversion formula for each result.

Formula & Calculations

Formula

°F = °C × 9/5 + 32, K = °C + 273.15, °R = °F + 459.67

Where:

°C=Celsius — water freezes at 0°C, boils at 100°C
°F=Fahrenheit — water freezes at 32°F, boils at 212°F
K=Kelvin — absolute zero is 0K, water freezes at 273.15K
°R=Rankine — absolute zero is 0°R, water freezes at 491.67°R

Assumptions

All conversions follow standard thermodynamic temperature scale definitions.
Negative Kelvin or Rankine values are physically impossible (below absolute zero), but the calculator allows them for mathematical completeness.
The Celsius-to-Kelvin conversion uses the exact offset of 273.15.

Calculation Examples

Example 1

Inputs:100°C to °F

Result:212°F

°F = 100 × 9/5 + 32 = 180 + 32 = 212°F.

Example 2

Inputs:32°F to °C

Result:0°C

°C = (32 - 32) × 5/9 = 0°C.

Example 3

Inputs:0K to °C

Result:-273.15°C

°C = 0 - 273.15 = -273.15°C (absolute zero).

Frequently Asked Questions

What is the Rankine scale used for?

The Rankine scale is an absolute temperature scale like Kelvin but uses Fahrenheit-sized degrees. It is mainly used in some engineering fields in the United States, particularly in thermodynamics calculations.

What is absolute zero?

Absolute zero is the lowest possible temperature: 0 Kelvin, -273.15°C, -459.67°F, or 0°R. At this temperature, molecular motion theoretically stops.

How do I convert between temperature scales?

Each scale has a conversion formula. From Celsius: °F = °C × 9/5 + 32, K = °C + 273.15, °R = (°C + 273.15) × 9/5. Our calculator shows the exact formula used for each conversion.