temperatures.com
Converters

Temperature Conversion

Three scales, six conversions, one page. Pick a converter below, or use the universal converter to see all three scales at once.

All temperature converters

Celsius to Fahrenheit Fahrenheit to Celsius Celsius to Kelvin Kelvin to Celsius Fahrenheit to Kelvin Kelvin to Fahrenheit Celsius to Rankine Rankine to Celsius Fahrenheit to Rankine Rankine to Fahrenheit Kelvin to Rankine Rankine to Kelvin

Which scale is which?

The four scales in one breath

  • Celsius (°C) - water freezes at 0, boils at 100. Used almost everywhere.
  • Fahrenheit (°F) - freezes at 32, boils at 212. Used in the United States.
  • Kelvin (K) - Celsius shifted so 0 sits at absolute zero. The language of science.
  • Rankine (°R) - Fahrenheit's absolute twin, still used in US engineering.

Want the full story of the anchor points? See freezing points across the scales and boiling points across the scales.

Conversion questions, answered

What is the fastest way to convert Celsius to Fahrenheit in your head?
Double the Celsius number and add 30 - close enough for weather. The exact method: multiply by 9/5 (or 1.8) and add 32.
Which countries still use Fahrenheit?
The United States plus a handful of territories and small nations, including the Cayman Islands, Liberia, Belize and Palau. Nearly everyone else reports temperatures in Celsius.
Do Kelvin and Rankine use a degree symbol?
Kelvin does not - water boils at 373.15 K, never °K. Rankine conventionally keeps the symbol, written °R.

Weather unit converters

Wind speed (mph · km/h · knots) Pressure (hPa · inHg · psi) Rainfall (mm · inches) Humidity to dew point UV index

All conversion formulas

ConversionFormula
Celsius to Fahrenheit °F = (°C × 9/5) + 32
Fahrenheit to Celsius °C = (°F − 32) × 5/9
Celsius to Kelvin K = °C + 273.15
Kelvin to Celsius °C = K − 273.15
Fahrenheit to Kelvin K = (°F + 459.67) × 5/9
Kelvin to Fahrenheit °F = (K × 9/5) − 459.67
Celsius to Rankine °R = (°C + 273.15) × 9/5
Rankine to Celsius °C = (°R − 491.67) × 5/9
Fahrenheit to Rankine °R = °F + 459.67
Rankine to Fahrenheit °F = °R − 459.67
Kelvin to Rankine °R = K × 1.8
Rankine to Kelvin K = °R ÷ 1.8

Reference temperatures across all three scales

Reference point°C°FK
Absolute zero -273.15 -459.67 0
Arctic winter day -30 -22 243.15
Home freezer -18 -0.4 255.15
Water freezes / ice melts 0 32 273.15
Refrigerator 3 37.4 276.15
Cool spring day 10 50 283.15
Comfortable room 21 69.8 294.15
Summer afternoon 30 86 303.15
Normal body temperature 37 98.6 310.15
Hot bath 40 104 313.15
Death Valley record heat 56.7 134.06 329.85
Water boils (sea level) 100 212 373.15
Moderate oven 180 356 453.15

Celsius, Fahrenheit and Kelvin in one minute

Celsius anchors 0° to water's freezing point and 100° to its boiling point at sea level - the scale used almost everywhere on Earth. Fahrenheit, used in the United States and a few other countries, places freezing at 32°F and boiling at 212°F, giving finer-grained degrees for everyday weather. Kelvin is the scientific scale: same degree size as Celsius, but starting at absolute zero (-273.15°C), so it never goes negative.

Weather in the US is reported in Fahrenheit; nearly everywhere else uses Celsius. Every city page on this site shows both - use the °F/°C toggle in the header to switch instantly.