Temperature Converter

Fahrenheit to Celsius quick reference

Fahrenheit	Celsius
32°F (freezing)	0°C
50°F	10°C
68°F (room temp)	20°C
98.6°F (body temp)	37°C
100°F	37.8°C
212°F (boiling)	100°C

How the conversion works

To convert Celsius to Fahrenheit: multiply by 9/5 (or 1.8) and add 32 °F = (°C × 9/5) + 32. To convert Fahrenheit to Celsius: subtract 32, then multiply by 5/9 °C = (°F − 32) × 5/9. Kelvin uses the same size degree as Celsius, just offset so that 0 K is absolute zero: K = °C + 273.15, meaning 0°C = 273.15 K and 100°C = 373.15 K.

Where each scale is actually used

Fahrenheit is used for everyday weather and home thermostats almost exclusively in the US (and a few territories); nearly every other country reports weather and sets ovens in Celsius. Cooking is a common source of confusion for anyone using recipes from abroad a US oven set to 350°F is 177°C, and a "gas mark 4" oven used in some UK recipes is about 180°C (356°F). Kelvin isn't used for weather or cooking at all; it's reserved for scientific and engineering contexts physics, chemistry, and astronomy because it has no negative numbers and starts at absolute zero, the theoretical point where molecular motion stops.

FAQ

What is a normal body temperature?
Normal human body temperature is often cited as 98.6°F (37°C), though healthy body temperature actually varies by person and time of day, typically ranging from about 97°F to 99°F (36.1°C to 37.2°C).

Why does science use Kelvin instead of Celsius?
Kelvin starts at absolute zero, the coldest temperature theoretically possible, so it never goes negative. That makes it far more convenient for scientific formulas like the ideal gas law where a negative temperature value would produce nonsensical results.

What temperature should I set my oven if a recipe uses Celsius?
Multiply the Celsius value by 9/5 and add 32. For example, a recipe calling for 200°C converts to 392°F, which most people round to 400°F the nearest common oven dial setting.

Why do the US and almost everyone else use different temperature scales?
Fahrenheit was developed in the early 1700s and adopted early by English-speaking countries; most of the world switched to the metric system (and Celsius with it) during the 19th and 20th centuries, but the US never made the full switch for everyday use.

At what temperature does water freeze and boil in each scale?
Water freezes at 32°F / 0°C / 273.15 K and boils at 212°F / 100°C / 373.15 K at standard sea-level atmospheric pressure. Boiling point drops at higher altitudes, which is why high-altitude cooking instructions often adjust times and temperatures.

Is there a quick mental-math shortcut for Celsius to Fahrenheit?
A rough estimate is to double the Celsius value and add 30 (instead of the exact ×1.8 and +32) it's close enough for a quick weather check, though this tool gives the exact figure when precision matters.