Celsius, Fahrenheit or Kelvin — this converter translates between all three temperature scales with exact formulas. It also guards against impossible inputs: anything below absolute zero (−273.15 °C) is rejected, because no such temperature can exist.
Converted temperature
77.00
All three scales are linear, so conversions are exact:
°F = (°C × 9/5) + 32 · °C = (°F − 32) × 5/9 · K = °C + 273.15
Celsius and Kelvin share the same degree size — Kelvin is just Celsius shifted so that 0 K is absolute zero. Fahrenheit's degree is smaller (5/9 of a Celsius degree) with its zero placed 32 degrees below water's freezing point.
Converted temperature is shown to two decimal places, which is plenty — most thermometers aren't more precise than 0.1°. The conversion used line shows the per-degree factor for the selected pair.
If your input was rejected, it fell below absolute zero. Double-check the scale you selected — a common mistake is entering a Celsius value while Fahrenheit is selected.
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Content last reviewed on 2026-10-06.