Convert -4°F to Celsius
Temperature converter
-4°F equals
-20°C
Freezing: Below the freezing point of water
How to convert -4°F to °C
Follow these steps to check the answer yourself.
- 1
Write the conversion formula
To convert Fahrenheit to Celsius, subtract 32 and multiply by 5/9.
°C = (°F − 32) × 5/9
- 2
Substitute the Fahrenheit value
Replace °F with -4.
°C = ((-4) − 32) × 5/9
- 3
Subtract 32
Work out the bracket first.
(-4) − 32 = -36
- 4
Multiply by 5/9
Scale the result to Celsius.
(-36) × 5/9 = -20
Answer: -4°F = -20°C
-4°F and nearby temperatures
Fahrenheit values from -9°F to 1°F converted to Celsius and Kelvin. Linked values open their own conversion page.
| Fahrenheit | Celsius | Kelvin |
|---|---|---|
| -9°F | -22.78°C | 250.37 K |
| -8°F to °C | -22.22°C | 250.93 K |
| -7°F | -21.67°C | 251.48 K |
| -6°F to °C | -21.11°C | 252.04 K |
| -5°F to °C | -20.56°C | 252.59 K |
| -4°F (this page) | -20°C | 253.15 K |
| -3°F | -19.44°C | 253.71 K |
| -2°F to °C | -18.89°C | 254.26 K |
| -1°F | -18.33°C | 254.82 K |
| 0°F to °C | -17.78°C | 255.37 K |
| 1°F | -17.22°C | 255.93 K |
Fahrenheit to Celsius conversion chart
Common temperatures from -40°F to 450°F. Bookmark or print this chart for quick reference.
| °F | °C |
|---|---|
| -40°F | -40°C |
| -20°F | -28.89°C |
| 0°F | -17.78°C |
| 10°F | -12.22°C |
| 20°F | -6.67°C |
| 32°F | 0°C |
| 40°F | 4.44°C |
| 50°F | 10°C |
| °F | °C |
|---|---|
| 60°F | 15.56°C |
| 70°F | 21.11°C |
| 80°F | 26.67°C |
| 90°F | 32.22°C |
| 98.6°F | 37°C |
| 100°F | 37.78°C |
| 110°F | 43.33°C |
| 120°F | 48.89°C |
| °F | °C |
|---|---|
| 150°F | 65.56°C |
| 200°F | 93.33°C |
| 212°F | 100°C |
| 250°F | 121.11°C |
| 300°F | 148.89°C |
| 350°F | 176.67°C |
| 400°F | 204.44°C |
| 450°F | 232.22°C |
Is -4°F hot or cold?
-4°F (-20°C) reads as freezing on the thermometer: below the freezing point of water. Typical context: below freezing, winter weather.
-4°F is 36°F warmer than the point where the Celsius and Fahrenheit scales meet (-40°F), and 3.6°F cooler than a standard home freezer (-0.4°F).
Quick mental math
To estimate Fahrenheit to Celsius in your head, subtract 30 from the Fahrenheit value and halve it.
((-4) − 30) ÷ 2 = -17°C (exact answer: -20°C)
The shortcut is close for everyday temperatures but drifts further from the exact answer in very hot or very cold conditions.
To go the other way, use the Celsius to Fahrenheit converter: -20°C converts back to -4°F.
Frequently asked questions
What is -4°F in Celsius?
-4°F equals -20°C. This is calculated with the standard Fahrenheit to Celsius formula.
How do I convert -4 Fahrenheit to Celsius?
To convert Fahrenheit to Celsius, subtract 32 and multiply by 5/9. For -4°F the result is -20°C.
Is -4°F hot or cold?
-20°C is very cold - well below freezing. This is severe winter weather temperature.
What is the formula for Fahrenheit to Celsius conversion?
The formula is: °C = (°F − 32) × 5/9
Good to know
- Anders Celsius proposed his scale in 1742. It was originally inverted, with 0 for boiling water and 100 for freezing; the order was flipped soon after his death.
- Daniel Gabriel Fahrenheit introduced his scale in 1724. The United States and a handful of other countries still use it for everyday temperatures.
- -40 is the only temperature that reads the same in Celsius and Fahrenheit.
- A change of 1°C or 1 K equals a change of 1.8°F.
Sources
- SI Units – Temperature (NIST (US National Institute of Standards and Technology))
Conversion formulas between °C, °F and K, and the 273.15 offset.
Written and checked by Abdul Manan.
Last updated . Results are for general information; see the disclaimer.