Fahrenheit to Celsius (°F to °C) Converter
A complete temperature conversion tool. Enter a value in any field to instantly convert between **Fahrenheit (°F)**, **Celsius (°C)**, and **Kelvin (K)**.
Calculation Steps:
Enter a value to see the step-by-step conversion.
How to Convert Fahrenheit to Celsius
Converting from Fahrenheit (°F) to Celsius (°C) is a common requirement for anyone traveling or working with scientific data. The conversion can be done with a simple formula or a quick mental math trick.
The Exact Formula
To convert Fahrenheit to Celsius, you first subtract 32 from the temperature, then multiply the result by 5/9 (or ~0.555...).
Example: Convert 70°F to °C.
1. 70 - 32 = 38
2. 38 × (5/9) = 21.11... °C
The Easy Mental Math Trick
For a quick estimate (especially for weather), you can use this simple trick:
Example: Convert 70°F to °C using the trick.
- Subtract 30:
70 - 30 = 40 - Divide by 2:
40 / 2 = 20 °C
This provides a very close and fast estimate (20°C) to the real answer (21.11°C).
Common Temperature Points
| Point | Fahrenheit (°F) | Celsius (°C) | Kelvin (K) |
|---|---|---|---|
| Water Boils | 212 °F | 100 °C | 373.15 K |
| Hot Day | 86 °F | 30 °C | 303.15 K |
| Water Freezes | 32 °F | 0 °C | 273.15 K |
| Absolute Zero | -459.67 °F | -273.15 °C | 0 K |
Frequently Asked Questions (FAQ)
What is the formula for Fahrenheit (°F) to Celsius (°C)?
The formula is: Celsius = (Fahrenheit - 32) × 5/9. (C = (F - 32) * 5/9).
What is 0 degrees Fahrenheit in Celsius?
0 °F is equal to -17.78 °C.
What is 32 degrees Fahrenheit in Celsius?
32 °F is exactly **0 °C**, which is the freezing point of water.
Formula (LaTeX) + variables + units
','
°C = (°F - 32) × 5/9
- No variables provided in audit spec.
- NIST — Weights and measures — nist.gov · Accessed 2026-01-19
https://www.nist.gov/pml/weights-and-measures - NIST — SI units — nist.gov · Accessed 2026-01-19
https://www.nist.gov/pml/owm/metric-si/si-units
Last code update: 2026-01-19
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