Temperature Converter
Convert temperatures between Celsius (°C), Fahrenheit (°F), Kelvin (K), and Rankine (°R) with step-by-step conversion formulas.
How to Use Temperature Converter
- Enter Temperature: Input any temperature value (positive or negative).
- Select Scales: Choose From and To temperature scales (Celsius, Fahrenheit, Kelvin, Rankine).
- Inspect Formula & Cards: Review the exact calculation formula and side-by-side overview cards for all 4 thermodynamic scales.
- Swap or Copy: Click Swap to invert scales or Copy to copy the converted temperature.
Frequently Asked Questions
What is the formula to convert Celsius to Fahrenheit?
°F = (°C × 9/5) + 32 (or °F = °C × 1.8 + 32). For example, 100 °C = (100 × 1.8) + 32 = 212 °F.
What is the formula to convert Fahrenheit to Celsius?
°C = (°F - 32) × 5/9. For example, 32 °F = (32 - 32) × 5/9 = 0 °C.
At what temperature are Celsius and Fahrenheit equal?
-40 degrees (-40 °C is exactly equal to -40 °F).
What is Absolute Zero?
Absolute Zero is the lowest possible thermodynamic temperature where molecular motion ceases: 0 Kelvin, -273.15 °C, -459.67 °F, and 0 °R.
What is the Rankine temperature scale?
Rankine (°R) is an absolute thermodynamic temperature scale using Fahrenheit degrees, where 0 °R is absolute zero and water freezes at 491.67 °R.
Can I convert negative temperatures?
Yes, negative numbers are fully supported across all scales.