Temperature Converter
Convert between Celsius, Fahrenheit, Kelvin, Rankine and 4 more units
Ideal room temperature
Understanding temperature scales
Three main scales: Celsius (°C), used in most countries; Fahrenheit (°F), used in the US and a few other countries; and Kelvin (K), the absolute scientific scale. 0 K is absolute zero (−273.15°C), the lowest possible temperature.
Conversion formulas
°F = (°C × 9/5) + 32 | °C = (°F − 32) × 5/9 | K = °C + 273.15. Practical benchmarks: 0°C = 32°F (freezing) | 37°C = 98.6°F (human body) | 100°C = 212°F (boiling) | 20°C = 68°F (comfortable room temperature).
Other historical scales
Rankine (°Ra): absolute scale based on Fahrenheit, used in American engineering. Delisle (°De): old inverted scale (100°De = 0°C). Newton (°N): created by Isaac Newton. Réaumur (°Ré): used in Europe in the 18th-19th centuries. Rømer (°Rø): the first calibrated scale in history.
Why choose OmniTools?
OmniTools brings together 20+ carefully crafted online tools built by our team. Every tool is designed to be fast, accurate and usable without sign-up. We believe essential everyday utilities — calculators, converters, generators — should be freely available with a clean interface and no intrusive ads. Our commitment: your data never leaves your browser.
Our tools are used daily by students, real-estate professionals, developers, designers, travelers and curious minds. Each tool comes with detailed documentation, formulas, reference values and practical tips to help you get the most out of it. We regularly ship new tools and improvements based on community feedback.
Frequently asked questions
Is this tool really free?
Yes, OmniTools is completely free, with no sign-up and no usage limit. No credit card required.
Is my data sent to a server?
No. All calculations and conversions run in your browser. Your data stays private on your device.
Does it work on mobile?
Yes, the interface is fully responsive and optimized for smartphones, tablets and desktops.
How often is the tool updated?
We continuously improve our tools based on user feedback to guarantee accuracy and reliability.