Temperature Converter
Celsius, Fahrenheit & Kelvin.
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Temperature Converter: Celsius, Fahrenheit & More
Temperature affects everything from our daily outfit choices to complex chemical reactions. While the US clings to Fahrenheit, the rest of the world uses Celsius, and scientists rely on Kelvin.
Our Universal Temperature Converter bridges these worlds. Beyond simple conversions, we provide specialized tools for the Kitchen (Gas Marks) and Health (Fever Guide).
Specialized Modes
Kitchen
Convert classic Gas Marks to Celsius/Fahrenheit. Also calculate adjustments for fan-assisted ovens (-20°C rule).
Health
Identify fevers quickly. Our color-coded guide shows Normal, Low Grade, and High Fever ranges for adults.
A Brief History of Heat
Daniel Gabriel Fahrenheit (1724): A German physicist who created the mercury thermometer. He set 0°F as the coldest temperature he could create in a lab (brine mixture) and 96°F as human body temperature (he was slightly off; it's ~98.6°F).
Anders Celsius (1742): A Swedish astronomer who proposed a scale based on water phases. Interestingly, he originally set 0° as boiling and 100° as freezing! It was reversed to the modern standard by Carl Linnaeus after Celsius's death.
Key Landmarks
| Point | Celsius | Fahrenheit |
|---|---|---|
| Absolute Zero | -273.15°C | -459.67°F |
| Freezing Water | 0°C | 32°F |
| Gas Mark 4 | 180°C | 350°F |
| Body Temp | 37°C | 98.6°F |
| Boiling Water | 100°C | 212°F |
Conversion Formulas
Celsius to Fahrenheit Most Common
(°C × 1.8) + 32 = °FFahrenheit to Celsius
(°F - 32) × 0.555 = °CCelsius to Kelvin
°C + 273.15 = KFrequently Asked Questions
What is Gas Mark 4 in Celsius?
Gas Mark 4 is 180°C (350°F). This is the standard moderate baking temperature for cakes and cookies.
How do I convert conventional oven temp to fan oven?
The general rule is to subtract 20°C. If a recipe calls for 200°C, set your fan oven to 180°C to avoid burning the food.
What constitutes a fever in adults?
A body temperature above 38°C (100.4°F) is generally considered a fever. A temperature above 39.4°C (103°F) is a high fever.
What is the formula to convert Celsius to Fahrenheit?
Multiply by 1.8 (or 9/5) and add 32. Formula: (°C × 1.8) + 32 = °F. Example: 20°C × 1.8 = 36 + 32 = 68°F.
How is 'Real Feel' or Heat Index calculated?
Heat Index combines air temperature and relative humidity to determine how hot it actually feels. High humidity prevents sweat evaporation, making it feel hotter.
What is Absolute Zero?
Absolute Zero (0 Kelvin or -273.15°C) is the theoretical temperature at which atoms stop moving completely. It is the coldest possible temperature in the universe physics allows.
Is -40 degrees the same in Celsius and Fahrenheit?
Yes! -40°C is exactly equal to -40°F. This is the unique point where the two linear scales intersect.
Why does the US use Fahrenheit?
The US stuck with the British Imperial system while the rest of the world modernized to Metric. Fahrenheit remains popular in the US for weather because it offers a wider range of integers for comfortable temperatures.
What is the normal body temperature range?
Normal body temperature ranges from 36.1°C to 37.2°C (97°F to 99°F). It can vary by age, activity, and time of day.
What is Wind Chill?
Wind Chill measures how cold it feels on exposed skin due to wind stripping away body heat. It is only calculated when the temperature is below 10°C (50°F) and wind speed is above 4.8 km/h (3 mph).