Translate scales with different zero points
Temperature conversion differs from most unit conversion because Celsius, Fahrenheit, and Kelvin do not share the same zero point. A temperature must be shifted as well as scaled. That is why doubling a Celsius reading does not double its Fahrenheit equivalent.
Use this page for actual temperature readings such as weather, oven settings, refrigeration, laboratory conditions, and device specifications. Temperature intervals are a related but different idea: a change of 1°C equals a change of 1 K, while a change of 1°C equals a change of 1.8°F.
Celsius, Fahrenheit, and Kelvin formulas
FigureNest converts the source reading to Celsius as a common reference, then applies the destination scale equation.
Celsius to Fahrenheit: °F = (°C × 9/5) + 32.
Fahrenheit to Celsius: °C = (°F − 32) × 5/9.
Celsius to Kelvin: K = °C + 273.15.
Kelvin to Celsius: °C = K − 273.15.
Kelvin has no degree symbol; 0 K is absolute zero.
Conversions in real situations
Convert 68°F to Celsius.
68°F = 20°CSubtract 32 from 68 and multiply the remainder by 5/9.
Convert 180°C to Fahrenheit.
180°C = 356°FMultiply 180 by 9/5 and add 32. Real ovens may use rounded dial settings and cycle around the target.
Convert 25°C to Kelvin.
25°C = 298.15 KAdd 273.15. Celsius and Kelvin increments are the same size but start at different zero points.
Read the result in context
Weather apps may round to a whole degree, while scientific measurements can require decimal precision and calibrated sensors. Converting a rounded source does not restore information that was not measured.
Cooking conversions translate the stated temperature but cannot account for oven calibration, fan-assisted settings, rack position, cookware, or altitude. Follow safety guidance and check food doneness independently.
What this conversion does not decide
- Values below absolute zero are physically impossible and are rejected.
- The calculator converts temperature readings, not heat energy or temperature intervals.
- Sensor accuracy, calibration, and source rounding are outside the calculation.
- Cooking equipment may require its own conventional rounded setting.
Temperature questions
What is the formula for Celsius to Fahrenheit?
Multiply the Celsius temperature by 9/5, then add 32.
At what temperature are Celsius and Fahrenheit equal?
The two scales show the same numerical value at −40: −40°C equals −40°F.
Why does Kelvin not use a degree symbol?
Kelvin is an absolute thermodynamic scale. Its unit name and symbol are kelvin and K, without the word degree or a degree symbol.
What is absolute zero on each scale?
Absolute zero is 0 K, −273.15°C, or −459.67°F.
Can I use the result as an exact oven setting?
Use it as a temperature conversion, then choose the nearest available oven setting and account for fan-assisted guidance and the appliance’s calibration.