Temperature Conversion Formula

Convert temperatures between Celsius, Fahrenheit, and Kelvin using mathematical formulas. Evaluate conversion expressions for common temperature values.

Conversion

Detailed Explanation

Temperature Conversion Formulas

Three temperature scales are commonly used worldwide. The evaluator lets you type any conversion formula directly.

Celsius to Fahrenheit

F = C * 9/5 + 32

Examples:

0 * 9/5 + 32 = 32       (freezing point)
100 * 9/5 + 32 = 212    (boiling point)
37 * 9/5 + 32 = 98.6    (body temperature)
20 * 9/5 + 32 = 68      (room temperature)

Fahrenheit to Celsius

C = (F - 32) * 5/9

Examples:

(72 - 32) * 5/9 = 22.22   (comfortable indoor)
(98.6 - 32) * 5/9 = 37    (body temperature)
(451 - 32) * 5/9 = 232.78 (paper ignition)

Celsius to Kelvin

K = C + 273.15

Examples:

0 + 273.15 = 273.15     (freezing point)
-273.15 + 273.15 = 0    (absolute zero)
100 + 273.15 = 373.15   (boiling point)

Fahrenheit to Kelvin

Combine both formulas:

K = (F - 32) * 5/9 + 273.15

Example: 72 F to Kelvin:

(72 - 32) * 5/9 + 273.15 = 295.37

Quick Reference

Celsius Fahrenheit Kelvin
-40 -40 233.15
0 32 273.15
20 68 293.15
37 98.6 310.15
100 212 373.15

Use Case

A traveler converting weather forecasts between Celsius and Fahrenheit, or a scientist converting laboratory measurements to Kelvin.

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