Temperature Conversion
Temperature conversion allows you to change a temperature from one measurement scale to another. The most common temperature scales are Celsius, Fahrenheit, and Kelvin. Converting between them is useful in weather reports, cooking, science, education, travel, and everyday measurements.
Common Temperature Scales
Celsius (°C) is widely used around the world for weather and everyday temperature measurements. On the Celsius scale, water freezes at 0°C and boils at 100°C under standard atmospheric pressure.
Fahrenheit (°F) is commonly used for everyday temperatures in the United States. Water freezes at 32°F and boils at 212°F under standard atmospheric pressure.
Kelvin (K) is an absolute temperature scale commonly used in science. Unlike Celsius and Fahrenheit, Kelvin does not use a degree symbol. Zero Kelvin represents absolute zero.
Celsius to Fahrenheit
To convert Celsius to Fahrenheit, use this formula:
°F = (°C × 9/5) + 32
For example, to convert 25°C:
(25 × 9/5) + 32 = 77°F
Therefore, 25°C equals 77°F.
Fahrenheit to Celsius
To convert Fahrenheit to Celsius, use:
°C = (°F − 32) × 5/9
For example, to convert 68°F:
(68 − 32) × 5/9 = 20°C
Therefore, 68°F equals 20°C.
Celsius to Kelvin
To convert Celsius to Kelvin, add 273.15:
K = °C + 273.15
For example:
25 + 273.15 = 298.15 K
Therefore, 25°C equals 298.15 K.
Kelvin to Celsius
To convert Kelvin to Celsius, subtract 273.15:
°C = K − 273.15
For example:
300 − 273.15 = 26.85°C
Therefore, 300 K equals 26.85°C.
Fahrenheit to Kelvin
To convert Fahrenheit to Kelvin, first subtract 32, multiply by 5/9, and then add 273.15:
K = (°F − 32) × 5/9 + 273.15
For example:
(68 − 32) × 5/9 + 273.15 = 293.15 K
Therefore, 68°F equals 293.15 K.
Kelvin to Fahrenheit
To convert Kelvin to Fahrenheit, use:
°F = (K − 273.15) × 9/5 + 32
For example:
(300 − 273.15) × 9/5 + 32 = 80.33°F
Therefore, 300 K is approximately 80.33°F.
Common Temperature Conversions
| Celsius | Fahrenheit | Kelvin |
|---|---|---|
| −40°C | −40°F | 233.15 K |
| 0°C | 32°F | 273.15 K |
| 10°C | 50°F | 283.15 K |
| 20°C | 68°F | 293.15 K |
| 25°C | 77°F | 298.15 K |
| 30°C | 86°F | 303.15 K |
| 37°C | 98.6°F | 310.15 K |
| 100°C | 212°F | 373.15 K |
Why Is Temperature Conversion Useful?
Different countries, industries, and scientific fields use different temperature scales. A temperature converter makes it easier to understand measurements when a value is given in an unfamiliar unit.
For example, someone traveling between countries may need to convert weather temperatures between Celsius and Fahrenheit. In science, Kelvin is often used when calculations involve absolute temperature.
Important Temperature Points
Water freezes at 0°C, 32°F, and 273.15 K under standard atmospheric pressure. It boils at 100°C, 212°F, and 373.15 K under standard atmospheric pressure.
An important point to remember is that −40°C equals −40°F. This is the temperature at which the Celsius and Fahrenheit scales have the same numerical value.
Common Conversion Mistakes
One common mistake is forgetting the 32 in the Celsius-to-Fahrenheit or Fahrenheit-to-Celsius formulas. Another is treating Kelvin like Celsius and writing a degree symbol with it. Kelvin is written simply as K.
It is also important to use the correct conversion direction. Check the starting unit before applying a formula to avoid reversing the calculation.
Using a Temperature Converter
For a single simple conversion, the formulas can be used manually. When you need to convert several temperatures or work with decimal values, a temperature converter can save time and reduce arithmetic mistakes.
For scientific or technical work, keep enough decimal places during the calculation and round the final result according to the required level of precision.