C to F Converter

C to F chart

A quick-read chart rounded to the nearest whole degree Fahrenheit — the way forecasts and thermostats show it. Every whole degree from −9 °C to 50 °C is here, plus colder, hotter and oven temperatures. Select a value for the exact answer and the working.

Hot and oven temperatures

For a printable version, open the Celsius to Fahrenheit chart.

The C to F formula in one line

°F = °C × 1.8 + 32. Multiply by 1.8, then add 32. For example, 25 °C × 1.8 = 45, and 45 + 32 = 77 °F. That is the whole method; the converter above just does it without rounding. For the reasoning behind 1.8 and 32, see the formula explained.

Three ways to convert C to F in your head

1. Double it and add 30. Close for everyday weather and always within a few degrees between 0 °C and 25 °C:

2. Use the “mirror” pairs. A few temperatures read almost the same backwards: 16 °C ≈ 61 °F and 28 °C ≈ 82 °F. Add the anchors −40 °C = −40 °F, 0 °C = 32 °F, 10 °C = 50 °F, 20 °C = 68 °F, 30 °C = 86 °F and 37 °C ≈ 98.6 °F, and you can place almost any forecast.

3. Count in fives. Every 5 °C is exactly 9 °F. From 20 °C = 68 °F, 25 °C is 77 °F, 30 °C is 86 °F and 35 °C is 95 °F.

A rhyme many people learn when moving to a Celsius country: “Thirty is hot, twenty is nice, ten is cold and zero is ice.”

Everyday °C settings in °F

Thermostats, appliances and spa controls made for international markets often show only Celsius. Here are common set-points:

Hot tub safety guidance in the US is not to exceed 104 °F (40 °C). Laundry symbols use Celsius worldwide; the washing machine temperature chart explains each one.

Switching your phone or computer between °C and °F

• iPhone and iPad: Settings → General → Language & Region → Temperature. In the Weather app you can also open the menu (•••) on the city list and choose °C or °F.
• Mac: System Settings → General → Language & Region → Temperature.
• Android: open your weather app’s settings and choose the unit; the Google weather card in search results has a °C | °F switch.
• Windows: in the Weather app or MSN Weather, open Settings and choose Celsius or Fahrenheit.
• Cars and smart thermostats: look for “Units” in the settings menu; most can switch without affecting anything else.

Changing the display unit is often easier than converting each reading — but when someone sends you a temperature in the other scale, this C to F converter is quicker.

What to wear for a °C forecast

Reading a forecast in Celsius while travelling? This is a practical packing guide, with the Fahrenheit equivalent for reference:

Wind and humidity change how a temperature feels; see the feels-like temperature calculator for the full picture.

Why converted forecasts look slightly off

Weather apps round temperatures to whole degrees before showing them. Because one Celsius degree is 1.8 Fahrenheit degrees, converting an already-rounded number can be up to about 0.9 °F away from what an American forecast would show. For example, a forecast of 21 °C might really be anything from 20.5 °C to 21.4 °C, which is 68.9 °F to 70.5 °F — so one app says 69 °F and another 70 °F. Neither is wrong. When precision matters, convert the original reading, not a rounded one, and keep decimals until the end.

C to F in Excel, Google Sheets and code

• Excel or Google Sheets: =A1*9/5+32, or the built-in =CONVERT(A1,"C","F").
• JavaScript: const f = c * 9 / 5 + 32;
• Python: f = c * 9 / 5 + 32
• Calculator: type the Celsius value, × 1.8, + 32, =.

Use 9/5 rather than a rounded 1.8 only if your tool works in fractions — they are exactly equal, so both give identical results. To build a printable table for a custom range, try the printable temperature table generator.

C to F fast facts

• Water boils at 100 °C (212 °F) only at sea level; at 2,000 m it boils at about 93 °C (199 °F), which is why high-altitude cooking takes longer.
• Most people are comfortable indoors between about 18 °C and 24 °C (64–75 °F).
• Snow can fall when the air is a few degrees above freezing — up to about 2 °C (36 °F) — because flakes need time to melt.
• Ray Bradbury’s Fahrenheit 451, the temperature at which book paper catches fire, is about 233 °C.
• A 1 °C change is a 1.8 °F change, so a forecast that rises from 20 °C to 25 °C climbs 9 °F (68 °F to 77 °F).

Extreme temperatures in C and F

The record figures are those recognised by the World Meteorological Organization. Notice how the gap between the two scales grows with temperature: at −40 they meet, but at 56.7 °C the Fahrenheit number is more than twice as large.

C to F questions

More temperature tools

• Celsius to Fahrenheit converter
• F to C
• Fahrenheit to Celsius
• Printable chart
• Body temperature
• Oven temperatures