Instant conversion
Equivalent temperatures
Celsius
20 °C
°C = entered value
Fahrenheit
68 °F
°F = (°C × 9/5) + 32
Kelvin
293.15 K
K = °C + 273.15
Rankine
527.67 °R
°R = (°C + 273.15) × 9/5
Free temperature conversion calculator
Temperature Converter
A temperature converter changes a value between Celsius, Fahrenheit, Kelvin, and Rankine. Enter one temperature to see every equivalent value, the conversion formulas, and absolute-zero validation instantly.
No signup or uploads. Every calculation runs in your browser.
Enter a temperature
Decimal and negative values are supported when they are at or above absolute zero.
Physical minimum
Absolute zero is -273.15 °C, -459.67 °F, 0 K, or 0 °R.
How to use the temperature converter
Enter a temperature
Type a whole number or decimal temperature into the value field.
Choose its scale
Select Celsius, Fahrenheit, Kelvin, or Rankine as the source unit.
Read every conversion
The equivalent values and direct formulas update immediately.
Copy or reset
Copy all four values or restore the 20°C example in one click.
Temperature conversion FAQ
How do you convert Celsius to Fahrenheit?
Multiply the Celsius temperature by 9/5, then add 32. For example, 20°C becomes 68°F.
How do you convert Fahrenheit to Celsius?
Subtract 32 from the Fahrenheit temperature, then multiply by 5/9. For example, 68°F becomes 20°C.
What is absolute zero in each temperature scale?
Absolute zero is -273.15°C, -459.67°F, 0 K, or 0°R. A physical temperature cannot be lower.
Does Kelvin use a degree symbol?
No. Kelvin values use K without a degree symbol, such as 273.15 K for the freezing point of water.
What is the difference between Kelvin and Rankine?
Both begin at absolute zero. Kelvin uses Celsius-sized intervals, while Rankine uses Fahrenheit-sized intervals.
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