Temperature Converter
Convert temperatures between Celsius, Fahrenheit, and Kelvin instantly.
Temperature Converter
Temperature conversions use formulas, not simple multiplication factors. Kelvin and Rankine cannot go below absolute zero.
Celsius and Fahrenheit can use negative values.
Converted temperature
68 °F
20 °C = 68 °F
Original temperature
20 °C
Conversion direction
Celsius to Fahrenheit
Formula used
°F = (°C × 9/5) + 32
Rounded result
68 °F
Absolute zero check
Temperature is above absolute zero
Kelvin equivalent
293.15 K
Formula-based
Temperature scales use offsets and scale factors, not simple multipliers.
Absolute zero validation
Impossible values below absolute zero are flagged with readable errors.
Everyday and science use
Useful for weather, cooking, labs, HVAC, travel, and product specifications.
Dynamic Conversion Insights
Temperature Scales Explained
Celsius (°C)
Common globally and in science-adjacent everyday use.
Fahrenheit (°F)
Commonly used for weather and household temperatures in the United States.
Kelvin (K)
An absolute temperature scale used in science and engineering.
Rankine (°R)
An absolute Fahrenheit-based scale used in some engineering contexts.
Celsius vs Fahrenheit vs Kelvin
Celsius
Celsius uses 0 °C for water freezing and 100 °C for water boiling at standard pressure.
Fahrenheit
Fahrenheit uses 32 °F for water freezing and 212 °F for water boiling at standard pressure.
Kelvin
Kelvin starts at absolute zero and uses the same degree size as Celsius. It is written as K, without a degree symbol.
Why Temperature Uses Formulas
Different zero points
Celsius, Fahrenheit, and Kelvin do not start at the same zero point, so a simple multiplication factor is not enough.
Different step sizes
Celsius and Fahrenheit degrees are different sizes. A change of 5 °C equals a change of 9 °F.
Kelvin offset
Kelvin shares the Celsius step size but starts at absolute zero, so K = °C + 273.15.
Not like length or weight
Length and weight often convert with one factor. Temperature usually needs both an offset and a scale factor.
Common Temperature Conversion Examples
0 °C
= 32 °F
= 273.15 K
20 °C
= 68 °F
= 293.15 K
37 °C
= 98.6 °F
= 310.15 K
100 °C
= 212 °F
= 373.15 K
-40 °C
= -40 °F
= 233.15 K
0 K
= -273.15 °C
= -459.67 °F
20 °C in all temperature scales
| Scale | Symbol | Value |
|---|---|---|
| Celsius | °C | 20 |
| Fahrenheit | °F | 68 |
| Kelvin | K | 293.15 |
| Rankine | °R | 527.67 |
Click any row to set it as the target scale.
Practical Use Cases
Formula Explanation
°F = (°C × 9/5) + 32
°C = (°F − 32) × 5/9
K = °C + 273.15
°C = K − 273.15
K = (°F − 32) × 5/9 + 273.15
°F = (K − 273.15) × 9/5 + 32
°R = °F + 459.67
Temperature formulas use both an offset and a scale factor. The converter first maps the source temperature to Celsius, then converts Celsius into the target scale. Values below absolute zero are rejected instead of silently clamped.
Frequently Asked Questions
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