Convert Celsius (°C) to Fahrenheit (°F)

The formula to convert Celsius to Fahrenheit is: °F = (°C × 9/5) + 32. You can also write this as °F = (°C × 1.8) + 32. First, multiply the Celsius temperature by 1.8 (or 9/5), then add 32 to the result. For example, to convert 20°C: 20 × 1.8 = 36, then 36 + 32 = 68°F.

Celsius and Fahrenheit are equal at -40 degrees. This is the only point where both scales intersect. You can verify this with the formula: (-40 × 9/5) + 32 = -72 + 32 = -40°F. This unique intersection point is a fun mathematical fact that demonstrates the relationship between the two linear but differently scaled temperature systems.

0°C is equal to 32°F. This is the freezing point of water at standard atmospheric pressure and is one of the key reference points of the Celsius scale. In the Fahrenheit scale, 32°F was historically set as the freezing point of water. This is why the formula adds 32 as an offset, accounting for the different zero points of the two scales.

Normal human body temperature is approximately 37°C, which equals 98.6°F. However, modern research suggests the average body temperature has decreased slightly over time and may be closer to 36.6°C (97.9°F). Body temperature varies throughout the day and from person to person, with a normal range typically between 36.1°C (97°F) and 37.2°C (99°F).

The United States continues to use Fahrenheit largely due to historical inertia and the cost of transitioning. The Fahrenheit scale was the standard in the English-speaking world when the US was founded. Attempts to switch to Celsius in the 1970s through the Metric Conversion Act were voluntary and ultimately unsuccessful. Most Americans are accustomed to Fahrenheit for weather and cooking, making a full transition culturally and economically challenging.