How to convert Celsius, Fahrenheit and Kelvin
The three everyday temperature scales are linked by simple formulas. Celsius is used by most of the world, Fahrenheit mainly in the United States, and Kelvin in science (it never goes negative). This converter shows all three at once so you never have to do the arithmetic by hand.
The formulas
- °C to °F: °F = °C × 9/5 + 32
- °F to °C: °C = (°F − 32) × 5/9
- °C to K: K = °C + 273.15
- K to °C: °C = K − 273.15
Quick mental shortcuts
For a rough °C→°F in your head, double the Celsius and add 30 (25 °C → about 80 °F; the exact answer is 77). It's close enough for weather. The scales cross at −40°, where Celsius and Fahrenheit read the same number.
Celsius to Fahrenheit and Kelvin chart: −20 to 45 °C
Every whole degree across the everyday range — weather, rooms, water and body temperature.
| °C | °F | K |
|---|---|---|
| -20 °C | -4 °F | 253.15 K |
| -19 °C | -2.2 °F | 254.15 K |
| -18 °C | -0.4 °F | 255.15 K |
| -17 °C | 1.4 °F | 256.15 K |
| -16 °C | 3.2 °F | 257.15 K |
| -15 °C | 5 °F | 258.15 K |
| -14 °C | 6.8 °F | 259.15 K |
| -13 °C | 8.6 °F | 260.15 K |
| -12 °C | 10.4 °F | 261.15 K |
| -11 °C | 12.2 °F | 262.15 K |
| -10 °C | 14 °F | 263.15 K |
| -9 °C | 15.8 °F | 264.15 K |
| -8 °C | 17.6 °F | 265.15 K |
| -7 °C | 19.4 °F | 266.15 K |
| -6 °C | 21.2 °F | 267.15 K |
| -5 °C | 23 °F | 268.15 K |
| -4 °C | 24.8 °F | 269.15 K |
| -3 °C | 26.6 °F | 270.15 K |
| -2 °C | 28.4 °F | 271.15 K |
| -1 °C | 30.2 °F | 272.15 K |
| 0 °C | 32 °F | 273.15 K |
| 1 °C | 33.8 °F | 274.15 K |
| °C | °F | K |
|---|---|---|
| 2 °C | 35.6 °F | 275.15 K |
| 3 °C | 37.4 °F | 276.15 K |
| 4 °C | 39.2 °F | 277.15 K |
| 5 °C | 41 °F | 278.15 K |
| 6 °C | 42.8 °F | 279.15 K |
| 7 °C | 44.6 °F | 280.15 K |
| 8 °C | 46.4 °F | 281.15 K |
| 9 °C | 48.2 °F | 282.15 K |
| 10 °C | 50 °F | 283.15 K |
| 11 °C | 51.8 °F | 284.15 K |
| 12 °C | 53.6 °F | 285.15 K |
| 13 °C | 55.4 °F | 286.15 K |
| 14 °C | 57.2 °F | 287.15 K |
| 15 °C | 59 °F | 288.15 K |
| 16 °C | 60.8 °F | 289.15 K |
| 17 °C | 62.6 °F | 290.15 K |
| 18 °C | 64.4 °F | 291.15 K |
| 19 °C | 66.2 °F | 292.15 K |
| 20 °C | 68 °F | 293.15 K |
| 21 °C | 69.8 °F | 294.15 K |
| 22 °C | 71.6 °F | 295.15 K |
| 23 °C | 73.4 °F | 296.15 K |
| °C | °F | K |
|---|---|---|
| 24 °C | 75.2 °F | 297.15 K |
| 25 °C | 77 °F | 298.15 K |
| 26 °C | 78.8 °F | 299.15 K |
| 27 °C | 80.6 °F | 300.15 K |
| 28 °C | 82.4 °F | 301.15 K |
| 29 °C | 84.2 °F | 302.15 K |
| 30 °C | 86 °F | 303.15 K |
| 31 °C | 87.8 °F | 304.15 K |
| 32 °C | 89.6 °F | 305.15 K |
| 33 °C | 91.4 °F | 306.15 K |
| 34 °C | 93.2 °F | 307.15 K |
| 35 °C | 95 °F | 308.15 K |
| 36 °C | 96.8 °F | 309.15 K |
| 37 °C | 98.6 °F | 310.15 K |
| 38 °C | 100.4 °F | 311.15 K |
| 39 °C | 102.2 °F | 312.15 K |
| 40 °C | 104 °F | 313.15 K |
| 41 °C | 105.8 °F | 314.15 K |
| 42 °C | 107.6 °F | 315.15 K |
| 43 °C | 109.4 °F | 316.15 K |
| 44 °C | 111.2 °F | 317.15 K |
| 45 °C | 113 °F | 318.15 K |
Oven temperatures: Celsius to Fahrenheit
Recipes from different countries give oven heat in different scales. Fan ovens usually run about 20 °C hotter than conventional ones, so reduce by that much for a fan oven.
| °C | °F | °C | °F |
|---|---|---|---|
| 100 °C | 212 °F | 190 °C | 374 °F |
| 110 °C | 230 °F | 200 °C | 392 °F |
| 120 °C | 248 °F | 210 °C | 410 °F |
| 130 °C | 266 °F | 220 °C | 428 °F |
| 140 °C | 284 °F | 230 °C | 446 °F |
| 150 °C | 302 °F | 240 °C | 464 °F |
| 160 °C | 320 °F | 250 °C | 482 °F |
| 170 °C | 338 °F | 260 °C | 500 °F |
| 180 °C | 356 °F |
Temperatures worth remembering
Water freezes at 0 °C (32 °F) and boils at 100 °C (212 °F) at sea level. Normal human body temperature is about 37 °C (98.6 °F), and comfortable room temperature is around 20–22 °C (68–72 °F).
What is 22 °C in Kelvin?
295.15 K. Add 273.15 to any Celsius temperature to get Kelvin. 22 °C is also 71.6 °F — a comfortable room temperature.
What is 80 °C in Kelvin?
353.15 K (80 + 273.15), which is 176 °F.
What is 298 K in Fahrenheit?
76.73 °F. First subtract 273.15 to get 24.85 °C, then multiply by 9/5 and add 32. 298 K is roughly standard "room temperature" in chemistry.
What is 209 °C in Fahrenheit?
408.2 °F — multiply by 1.8 and add 32. That's a hot oven, close to the common 200 °C / 400 °F setting.
How do I convert Celsius to Fahrenheit?
Multiply the Celsius value by 9/5 (1.8) and add 32. For example, 25 °C × 1.8 = 45, plus 32 = 77 °F. Enter any value above and the calculator does it instantly, along with Kelvin.
How do I convert Fahrenheit to Celsius?
Subtract 32 from the Fahrenheit value, then multiply by 5/9. For example, (98.6 − 32) × 5/9 = 37 °C. Switch the "from" unit to Fahrenheit above to convert this direction.
What is normal body temperature in Celsius and Fahrenheit?
About 37 °C, which is 98.6 °F. A reading above roughly 38 °C (100.4 °F) is generally considered a fever, though normal varies a little between people and times of day.
What is 0 Kelvin?
0 K is absolute zero — the lowest possible temperature, equal to −273.15 °C or −459.67 °F. Nothing can get colder, because it's the point where molecular motion stops.
At what temperature are Celsius and Fahrenheit equal?
At −40°: −40 °C equals exactly −40 °F. It's the one point where the two scales give the same number, which makes it a handy fact to remember.