Celsius to Fahrenheit (°C to °F) Converter
A complete temperature conversion tool. Enter a value in any field to instantly convert between **Celsius (°C)**, **Fahrenheit (°F)**, and **Kelvin (K)**.
Calculation Steps:
Enter a value to see the step-by-step conversion.
How to Convert Celsius to Fahrenheit
Converting from Celsius (°C) to Fahrenheit (°F) is essential for anyone used to metric temperatures traveling in the US. The conversion can be done with an exact formula or a quick mental math trick for weather.
The Exact Formula
To convert Celsius to Fahrenheit, you first multiply the Celsius temperature by 9/5 (or 1.8), then add 32.
Example: Convert 25°C (room temperature) to °F.
1. 25 × (9/5) = 45
2. 45 + 32 = 77 °F
The Easy Mental Math Trick
For a quick estimate (great for weather), you can **"double it and add 30"**.
Example: Convert 25°C to °F using the trick.
- Double it:
25 × 2 = 50 - Add 30:
50 + 30 = 80 °F
This provides a very fast and close estimate (80°F) to the real answer (77°F).
Key Temperature Points
| Point | Celsius (°C) | Fahrenheit (°F) | Kelvin (K) |
|---|---|---|---|
| Water Boils | 100 °C | 212 °F | 373.15 K |
| Hot Day | 30 °C | 86 °F | 303.15 K |
| Water Freezes | 0 °C | 32 °F | 273.15 K |
| Absolute Zero | -273.15 °C | -459.67 °F | 0 K |
Frequently Asked Questions (FAQ)
What is the formula for Celsius (°C) to Fahrenheit (°F)?
The formula is: Fahrenheit = (Celsius × 9/5) + 32. You can also use 1.8 instead of 9/5.
What is the quick way to convert °C to °F?
The fastest mental math trick is to **double the Celsius temperature and add 30**. (e.g., 10°C * 2 = 20, + 30 = 50°F). The exact answer is 50°F, so this trick is very accurate for common temperatures.
What is 0 degrees Celsius in Fahrenheit?
0°C is exactly **32°F**, which is the freezing point of water.
Formula (LaTeX) + variables + units
','
°F = (°C × 9/5) + 32
- 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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