Temperature Converter

Convert temperature units between Celsius, Fahrenheit, and Kelvin scales. Find standard formulas, absolute zero, melting points, and conversion steps.

Celsius (°C)
Fahrenheit (°F)
Kelvin (K)
Common references: Water freezes at 0°C / 32°F. Water boils at 100°C / 212°F. Body temp ~37°C / 98.6°F.

About the Temperature Converter

Temperature scales differ globally, with Celsius being the standard metric unit, Fahrenheit used primarily in the United States, and Kelvin used in scientific research. Our free online Temperature Converter helps you convert temperatures between these three scales instantly, displaying accurate conversions.

The calculator applies standard thermal physics equations: F = C × 9/5 + 32, C = (F - 32) × 5/9, K = C + 273.15, and C = K - 273.15. The converter handles negative temperatures and absolute zero limits correctly.

Frequently Asked Questions

❓ What is the formula to convert Celsius to Fahrenheit?

The formula is: F = (C * 9/5) + 32. For example, to convert 20°C to Fahrenheit: (20 * 1.8) + 32 = 36 + 32 = 68°F.

❓ What is the formula to convert Fahrenheit to Celsius?

The formula is: C = (F - 32) * 5/9. For example, to convert 98.6°F to Celsius: (98.6 - 32) * 5/9 = 66.6 * 5/9 = 37°C.

❓ What is Kelvin and when is it used?

Kelvin (K) is the primary unit of temperature in the International System of Units (SI), starting at absolute zero (the point where all molecular motion stops, -273.15°C). It is widely used in physics and chemistry because it contains no negative values.

❓ At what temperature do Celsius and Fahrenheit equal the same value?

Celsius and Fahrenheit scales are equal at exactly -40 degrees (i.e., -40°C is equal to -40°F).