Temperature Converter

1. 1Type a temperature into any of the four boxes.
2. 2The other three update immediately.
3. 3Use the reference points below for a quick sanity check.

Temperature is the odd one out among unit conversions, because these scales have different zero points as well as different step sizes. That is why you cannot convert by multiplying alone — you have to shift as well as scale.

Celsius and Kelvin share a step size and differ only in where zero sits: 0 °C is 273.15 K. Fahrenheit uses a step five-ninths the size, with its zero further down again. Rankine is to Fahrenheit what Kelvin is to Celsius — an absolute scale using Fahrenheit-sized degrees.

Absolute zero is the floor: −273.15 °C, −459.67 °F, or 0 K. Values below it are physically impossible, and the tool flags them rather than converting nonsense.

Converting a 180 °C oven temperature

1. 180 × 9/5 = 324
2. 324 + 32 = 356

Result: 356 °F, or 453.15 K.

• Remember temperature needs a shift as well as a scale, so a simple multiplication will be wrong.
• Use −40, where Celsius and Fahrenheit agree, as a quick sanity check.
• For a rough mental answer, double the Celsius figure and add 30.
• Kelvin is written without a degree sign: 300 K, not 300 °K.

• Recipe conversions: cups to grams, ounces, spoons and oven temperatures
• Fever temperatures in Celsius and Fahrenheit
• Celsius to Fahrenheit in your head: the shortcut and where it fails