Celsius to Fahrenheit
Convert Celsius to Fahrenheit instantly.
How to Convert Celsius to Fahrenheit
To convert Celsius to Fahrenheit, use the formula: °F = (°C × 9/5) + 32. Celsius is the standard temperature scale used in almost every country in the world for weather, cooking, and science. Fahrenheit is used primarily in the United States. Knowing key reference points helps build intuition: 0°C = 32°F (water freezes), 20°C = 68°F (comfortable room temperature), 37°C = 98.6°F (normal body temperature), 100°C = 212°F (water boils at sea level).
Celsius to Fahrenheit Reference Chart
Common conversions: -10°C = 14°F · 0°C = 32°F · 10°C = 50°F · 20°C = 68°F · 25°C = 77°F · 30°C = 86°F · 37°C = 98.6°F · 40°C = 104°F · 100°C = 212°F.
Frequently Asked Questions
What is the formula for Celsius to Fahrenheit?
°F = (°C × 9/5) + 32. This can also be written as °F = (°C × 1.8) + 32. For a quick mental approximation, double the Celsius temperature and add 30 — this gives a result within a few degrees for most everyday temperatures (e.g., 20°C → 20×2+30 = 70°F, actual answer is 68°F).
What is 30 degrees Celsius in Fahrenheit?
(30 × 9/5) + 32 = 54 + 32 = 86°F. A temperature of 30°C is a hot summer day — uncomfortably warm for most people without air conditioning, roughly equivalent to a warm July day in the southern United States.
What temperature is the same in Celsius and Fahrenheit?
-40°C equals exactly -40°F. This is the only point where the two scales intersect. Below -40, Celsius readings are numerically higher than Fahrenheit; above -40, Fahrenheit readings are always higher than Celsius.
Why does the US use Fahrenheit while most countries use Celsius?
The US adopted Fahrenheit in the 18th century and never transitioned to Celsius, while most other countries switched as part of metric system adoption in the 19th and 20th centuries. Fahrenheit was proposed by Daniel Gabriel Fahrenheit in 1724 and was widely used before the metric system existed. The US Metric Conversion Act of 1975 encouraged but did not mandate switching, so everyday temperature usage in the US remained in Fahrenheit.