Celsius to Fahrenheit Converter
Convert °C to °F (and back) instantly — with the formula, everyday reference points, and a quick chart.
Convert
Everyday reference points
| °C | °F |
|---|
The Formula: (°C × 9/5) + 32
Unlike length or weight, temperature conversion has an offset — you can't just multiply. The 9/5 handles the different degree sizes (180 Fahrenheit degrees between freezing and boiling vs 100 Celsius degrees), and the +32 aligns the different zero points. Forget the +32 and 20°C becomes 36°F instead of 68°F — the classic mistake.
Quick Conversion Chart
| °C | °F | Feels like |
|---|---|---|
| −10 | 14 | Bitter cold |
| 0 | 32 | Freezing |
| 10 | 50 | Chilly |
| 20 | 68 | Room temp |
| 30 | 86 | Hot |
| 37 | 98.6 | Body temp |
| 100 | 212 | Boiling |
Worked Example: 20°C
A pleasant spring day in Celsius → Fahrenheit
Step 1: Multiply by 9/5: 20 × 1.8 = 36.
Step 2: Add 32: 36 + 32 = 68°F.
Sanity check: 20°C is room temperature, and 68°F is room temperature — matches.
Reverse: Fahrenheit to Celsius
Subtract 32, then multiply by 5/9: 98.6°F → (98.6 − 32) × 5/9 = 66.6 × 5/9 = 37°C. Mental shortcut: subtract 30, then halve — 80°F → 50 → 25°C (true: 26.7°C). Within a couple degrees, good enough for weather chat.
Everyday Reference Points
- −18°C / 0°F: standard freezer temperature.
- 0°C / 32°F: water freezes — the number every winter driver knows.
- 20°C / 68°F: comfortable room temperature.
- 37°C / 98.6°F: body temperature; 38°C / 100.4°F is generally a fever.
- 100°C / 212°F: water boils (at sea level).
- 175°C / 350°F: the most common oven setting in recipes.
Anchor a few of these and you'll rarely need the converter for weather: 0/32 freezing, 10/50 chilly, 20/68 pleasant, 30/86 hot. Everything else is interpolation.
My saved numbers reuse them in any calculator
Save a number once — like your rent or hourly rate — then just type its name instead of the number, in any calculator here. You can also type formulas like 5000 * 1.1 right into any box.
Saved only in this browser — nothing is sent to us.
Frequently Asked Questions
What is the formula for Celsius to Fahrenheit?
°F = (°C × 9/5) + 32. Reverse: °C = (°F − 32) × 5/9.
What is 20°C in Fahrenheit?
20°C = 68°F. Calculation: (20 × 9/5) + 32 = 36 + 32 = 68.
What is 0°C in Fahrenheit?
0°C = 32°F — the freezing point of water.
Why do two temperature scales exist?
Fahrenheit (1724) came first and stuck in the US; Celsius (1742) aligned 0/100 with water's freezing/boiling points and became the scientific and global standard. Both survive because changing a nation's thermometers, habits and building codes is enormously expensive.
What is normal body temperature in both scales?
98.6°F = 37°C — though modern research suggests the true average is slightly lower, around 97.7°F (36.5°C). Anything above 100.4°F (38°C) is generally considered a fever.