TooliniumThe Temperature Converter instantly converts between Celsius, Fahrenheit, Kelvin, and Rankine — the four most commonly used temperature scales in science…
Because Temperature Converter runs entirely in your browser, none of the files or numbers you enter are uploaded anywhere — everything is processed locally on your own device and cleared as soon as you close the tab.
The most widely used scale worldwide. Water freezes at 0°C and boils at 100°C at sea level. It's the standard for weather, cooking, and everyday measurements outside the US.
Used mainly in the United States. Water freezes at 32°F and boils at 212°F. Each Fahrenheit degree is smaller than a Celsius degree, which is why the numbers look larger.
The scientific standard, starting at absolute zero (0 K), the coldest temperature theoretically possible. Kelvin uses the same size step as Celsius, just shifted so it never goes negative.
An absolute scale like Kelvin, but sized in Fahrenheit degrees. It's mostly used in engineering and thermodynamics fields in the United States.
Absolute zero (0 K, -273.15°C) is the point where atomic motion theoretically stops entirely. It's the fixed reference point that makes the Kelvin scale useful in physics and chemistry.
Celsius and Fahrenheit can go negative, but Kelvin and Rankine cannot — they're absolute scales that start at the coldest possible point, so negative readings would be physically meaningless.
A fast rule of thumb: double the Celsius number and add 30 to get a rough Fahrenheit estimate. It's not exact, but close enough for everyday use like checking the weather.
Recipes from different countries often list oven temperatures in different scales — this converter is handy for following a recipe written in a unit your oven doesn't display.
Phone weather apps often default to the unit standard in your region, which is why travelers frequently need to convert between Celsius and Fahrenheit manually when checking forecasts abroad.
Body temperature readings are sometimes given in Fahrenheit (like 98.6°F normal) and sometimes in Celsius (37°C) depending on the country, making quick conversion useful for international medical contexts.
Most scientific publications and industrial processes standardize on Celsius or Kelvin, even in countries that use Fahrenheit for everyday life, so conversions are a routine part of technical work.
Use the units provided by the converter, such as Celsius, Fahrenheit and Kelvin, for quick conversions.
The calculations use standard temperature conversion formulas and are suitable for normal everyday conversions.
Once the page is loaded, the conversion itself runs in your browser.