Konverter
Temperature Converter
The Temperature Converter instantly translates temperature values between Celsius (°C), Fahrenheit (°F), Kelvin (K), and Rankine (°R). It is useful for scientists, engineers, developers working with sensor data, and anyone dealing with international temperature specifications. Enter a value in any unit and all other scales update simultaneously.
What are the temperature scales?
Celsius (°C) is the scale used in science and everyday life in most of the world, with water freezing at 0°C and boiling at 100°C at sea level. Fahrenheit (°F) is used in the United States and a few other countries; water freezes at 32°F and boils at 212°F. Kelvin (K) is the SI base unit of thermodynamic temperature, starting at absolute zero (−273.15°C), the coldest theoretically possible temperature. Zero Kelvin equals −273.15°C or −459.67°F. Rankine (°R) is the Fahrenheit-based absolute scale used in some US engineering and thermodynamics contexts; absolute zero is 0°R and equals 0 K.
How does the converter work?
Each temperature scale is related to Kelvin through a fixed mathematical formula. The tool converts the input value to Kelvin as the intermediate representation, then derives all other scales from that canonical value. Celsius to Kelvin: K = °C + 273.15. Fahrenheit to Kelvin: K = (°F + 459.67) × 5/9. Rankine to Kelvin: K = °R × 5/9. The conversion results are displayed simultaneously in all four scales rounded to two decimal places. Absolute zero is enforced as the minimum valid input.
Typical Use Cases
- Converting sensor readings in °C from IoT devices to °F for US-based dashboards
- Converting recipe temperatures between Celsius (European ovens) and Fahrenheit (US recipes)
- Working with thermodynamic calculations that require absolute temperature in Kelvin
- Verifying temperature thresholds for hardware operating ranges specified in different units
Step-by-step Guide
- Step 1: Enter the temperature value in any of the four input fields.
- Step 2: The tool instantly calculates and displays the equivalent in all other scales.
- Step 3: Copy any result to your clipboard using the copy icon.
- Step 4: Clear and enter a new value to convert another temperature.
Example
Input
100 °C
Output
°F: 212 | K: 373.15 | °R: 671.67
Tips & Notes
- A quick mental formula for Celsius to Fahrenheit: double the °C value and add 30 – it is not exact but close enough for everyday estimates.
- Kelvin is always positive; if your calculation produces a negative Kelvin value, you have an error.
- Rankine is almost never used outside of US aerospace and mechanical engineering – stick to Kelvin for thermodynamic work in most fields.
Frequently Asked Questions
What is absolute zero in Celsius and Fahrenheit?
Absolute zero is 0 K, which equals −273.15°C or −459.67°F. It is the theoretical minimum temperature at which all thermal motion ceases.
Why does the US still use Fahrenheit?
The United States never completed the metrication process that most other countries underwent in the 1970s. Fahrenheit remains deeply embedded in everyday culture, weather reporting, and cooking despite Celsius being used in US science and medicine.
Is body temperature 37°C or 98.6°F?
Both are correct for the traditional average human body temperature, though modern research shows that the actual average is closer to 36.6°C (97.9°F). Individual variation is significant.
Temperature Converter
Convert temperatures between Kelvin, Celsius, Fahrenheit, Rankine, Delisle, Newton, Réaumur, and Rømer.
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