Accurately convert between Celsius, Fahrenheit, and Kelvin with animated alpaca temperature sensor effects.
Accurate conversion between Celsius, Fahrenheit and Kelvin
Accurately convert between Celsius, Fahrenheit, and Kelvin with animated alpaca temperature sensor effects. Use it for everyday work, development, learning, or quick verification.
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Most of the world uses Celsius (°C), while the United States uses Fahrenheit (°F) for weather forecasts, oven recipes, thermometers and many product specs, and science and engineering use Kelvin (K). This tool puts all three scales side by side. Type a number in any field and the other two update instantly, rounded to three decimal places, with a copy button for each.
There are only two formulas. Fahrenheit = Celsius × 1.8 + 32, so Celsius = (Fahrenheit − 32) ÷ 1.8. Kelvin = Celsius + 273.15. Celsius and Fahrenheit differ in both step size (a 1 °C difference equals 1.8 °F) and starting point (water freezes at 0 °C and 32 °F), which is why you cannot just multiply. Kelvin uses the same step size as Celsius but starts at absolute zero (−273.15 °C), so it has no negative values and is written simply as “K” without a degree sign.
Some reference points worth remembering: water freezes at 0 °C = 32 °F = 273.15 K and boils (at sea-level pressure) at 100 °C = 212 °F. Normal body temperature is about 37 °C = 98.6 °F, and a 38 °C fever threshold is about 100.4 °F. A typical oven setting of 180 °C is about 356 °F, while the common US recipe temperature of 350 °F is about 176.7 °C. And −40 °C equals exactly −40 °F, the only point where the two scales meet.
For quick mental math, estimate Fahrenheit as Celsius × 2 + 30; 25 °C comes out around 80 °F (actually 77 °F). Going the other way, use (Fahrenheit − 30) ÷ 2. The shortcut is off by only a few degrees around room temperature but drifts further as temperatures rise, so use the exact result here for cooking or medical purposes.
°F = °C × 1.8 + 32. For example, 30 °C = 30 × 1.8 + 32 = 86 °F.
37 °C = 98.6 °F, the common reference value for normal body temperature.
At −40: −40 °C is exactly −40 °F.
No. 0 K is absolute zero (−273.15 °C), the lowest temperature possible in theory.
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