Convert temperature between Celsius, Fahrenheit, Kelvin, and Rankine — with all three common scales shown at once.
Temperature scales are affine, not simple ratios: °F = °C × 9/5 + 32, K = °C + 273.15. Absolute zero is 0 K / −273.15 °C. General information only.
Unlike length or weight, temperature scales have different zero points, so you can't just multiply by a factor. Each conversion shifts and scales: Fahrenheit multiplies Celsius by 9/5 and adds 32; Kelvin just adds 273.15 (it shares Celsius's degree size but starts at absolute zero).
°F = °C × 9/5 + 32 · K = °C + 273.15
About 98.6 °F, which is 37 °C — the default here. Anything is convertible; these are just familiar reference points.
Science and engineering — it starts at absolute zero, so there are no negative temperatures, which makes physics formulas cleaner.
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Last reviewed: September 2026. Free to use, no signup — Temperature Converter by ToolWise Digital.
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