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-40 °C to °F
-40 °C = -40 °F
-40 degrees Celsius is -40 degrees Fahrenheit.
How to work it out
-40 × 9/5 + 32 = -40
Formula: °F = °C × 9/5 + 32
Other ways to write it
- In kelvin
- 233.15 K
Celsius to Fahrenheit (°C to °F) near -40
Full Celsius to Fahrenheit (°C to °F) chart → Fahrenheit to Celsius (°F to °C) →
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About the Unit Converter
The unit converter changes values between metric and imperial units for length, weight, temperature, digital data, area, and volume.
How to use it
- 1 Choose a category, such as length or temperature.
- 2 Pick the unit to convert from and the unit to convert to.
- 3 Type a value to see the converted result straight away.
Frequently asked questions
What is -40 °C in °F?
-40 degrees Celsius equals -40 degrees Fahrenheit. Worked out: -40 × 9/5 + 32 = -40.
How do I convert Celsius to Fahrenheit?
Multiply the Celsius value by 9/5 and add 32. For example, 20 °C × 9/5 + 32 = 68 °F.
How many centimetres are in an inch?
One inch is exactly 2.54 centimetres, and one foot is 30.48 centimetres.
Is a kilobyte 1,000 or 1,024 bytes?
In SI units a kilobyte (kB) is 1,000 bytes. A kibibyte (KiB) is 1,024 bytes. Some operating systems still use "KB" to mean 1,024 bytes.