Temperature Converter
Convert between Celsius, Fahrenheit, Kelvin and Rankine with instant results and high precision. Perfect for cooking, weather, science, and international communication.
Temperature Conversion Calculator
Convert between Celsius, Fahrenheit, Kelvin and Rankine with high precision
Common Temperature References
Click any reference to use as input
Popular Conversions
Temperature Scales
Conversion Formulas
When to Use Each Scale
Temperature Conversion Table
Common temperature conversions for quick reference
| Description | Celsius (°C) | Fahrenheit (°F) | Kelvin (K) |
|---|---|---|---|
| Absolute Zero | -273.15 | -459.67 | 0 |
| Dry Ice Sublimates | -78.5 | -109.3 | 194.65 |
| Water Freezes | 0 | 32 | 273.15 |
| Room Temperature | 20 | 68 | 293.15 |
| Human Body Temperature | 37 | 98.6 | 310.15 |
| Water Boils | 100 | 212 | 373.15 |
| Oven Temperature (Medium) | 175 | 347 | 448.15 |
| Paper Ignites | 233 | 451 | 506.15 |
Understanding Temperature Scales
History of Temperature Scales
The Celsius scale was developed by Anders Celsius in 1742, originally with 100° as the freezing point and 0° as the boiling point. The Fahrenheit scale, created by Daniel Gabriel Fahrenheit in 1724, was based on a mixture of ice, water, and salt. Kelvin, proposed by Lord Kelvin in 1848, is the absolute temperature scale used in science.
Absolute Zero and Temperature Scales
Absolute zero is the theoretical temperature at which all molecular motion stops. It's -273.15°C, -459.67°F, or 0K. The Kelvin and Rankine scales start at absolute zero, making them "absolute" temperature scales, while Celsius and Fahrenheit are "relative" scales based on water's phase changes.
Practical Applications
Temperature conversion is essential for cooking (recipes from different countries), weather forecasts when traveling, scientific research, engineering projects, and medical applications. Understanding these scales helps in international communication and ensures safety in various applications.
Frequently Asked Questions
Which temperature scale should I use?
Use Celsius for most international applications and science, Fahrenheit if you're in the US or dealing with US recipes, and Kelvin for scientific calculations involving absolute temperature measurements.
Why does the US use Fahrenheit?
The US adopted Fahrenheit early in its history, and the scale became entrenched in everyday life. Fahrenheit provides more precise whole numbers for everyday temperatures (0-100°F covers most weather conditions), making it practical for daily use in temperate climates.
What is the difference between Celsius and Centigrade?
"Centigrade" is the old name for the Celsius scale. In 1948, the scale was officially renamed "Celsius" to honor Anders Celsius. Both terms refer to the same temperature scale where water freezes at 0° and boils at 100°.
Can temperatures go below absolute zero?
Theoretically, no. Absolute zero represents the complete absence of thermal energy. However, in quantum mechanics, scientists have achieved "negative absolute temperatures" in very specific controlled conditions, which paradoxically represent extremely hot states, not cold ones.