Guides/Celsius ↔ Fahrenheit

Celsius to Fahrenheit explained

Weather apps, oven manuals, and travel forecasts switch between Celsius and Fahrenheit constantly. Temperature conversion is not a simple multiply — there is an offset because the zero points differ.

The formulas

°F = °C × 9/5 + 32 (or °C × 1.8 + 32)
°C = (°F − 32) × 5/9
Kelvin = °C + 273.15 (science / absolute scale)

Memory anchors

0 °C = 32 °F (freezing water)
10 °C ≈ 50 °F (cool)
20 °C ≈ 68 °F (mild room)
25 °C = 77 °F (warm)
37 °C ≈ 98.6 °F (body temperature — educational reference only, not medical advice)
100 °C = 212 °F (boiling water at standard pressure)

Worked examples

Travel forecast: 25 °C → 25 × 1.8 + 32 = 77 °F.
Cold morning: −5 °C → −5 × 1.8 + 32 = 23 °F.
Oven: 180 °C → 180 × 1.8 + 32 = 356 °F(often rounded to 350 °F in US recipes).
Reverse: 68 °F → (68 − 32) × 5/9 = 36 × 5/9 = 20 °C.

Common mistakes

Multiplying by 1.8 and forgetting to add 32.
Subtracting 32 after multiplying instead of before when converting °F → °C.
Assuming a “double it and add 30” rule is exact — it is only a rough estimate.

When to use which tool

Unit Converter (Temperature tab) — °C, °F, K instantly.
Metric ↔ imperial guide — length, weight, and volume too.
Mental °C/°F tricks — no calculator.
°F → °C quick formula.

Convert online

Use the freeUnit ConverterTemperature tab. Private, no signup.