Temperature Converter

The formula is F = (C x 9/5) + 32. To go the other direction, C = (F - 32) x 5/9. Fahrenheit is used for everyday weather in the United States; Celsius is standard for science and most of the world. For scientific work requiring absolute temperature, Kelvin adds 273.15 to the Celsius value (K = C + 273.15), so 0 K is absolute zero and there are no negative Kelvin values.

ASHRAE defines standard room temperature as 20-22 C (68-72 F) for comfort. For reference: body temperature is 37 C / 98.6 F; water freezes at 0 C / 32 F and boils at 100 C / 212 F at sea level; a moderate oven is around 175 C (350 F), and a hot oven is 230 C (450 F). These benchmarks help anchor any conversion you need to check.

Kelvin starts at absolute zero (-273.15 C), the coldest theoretically possible temperature, so it has no negative values. Gas-law formulas like PV = nRT require absolute temperature, and using Celsius would produce nonsensical negative results. Everyday examples: the surface of the sun is about 5,778 K, liquid nitrogen boils at 77 K, and a comfortable room is roughly 295 K.

-40 is the one point where both scales agree exactly. Key anchors: 0 C = 32 F, 100 C = 212 F, and body temperature 37 C = 98.6 F. For a quick estimate of any Celsius reading in Fahrenheit, double the Celsius value and add 30 (e.g., 22 C gives ~74 F; actual is 71.6 F). This rough method is close enough for weather but not precise enough for cooking.