Fahrenheit to Kelvin Conversion Calculator: Free Online Tool
Convert degrees Fahrenheit to kelvins with our free online temperature converter.
Fahrenheit to Kelvin Calculator
How to Use the Calculator:
- Enter the value you want to convert in the 'From' field (Fahrenheit).
- The converted value in Kelvin will appear automatically in the 'To' field.
- Use the dropdown menus to select different units within the Temperature category.
- Click the swap button (⇌) to reverse the conversion direction.
How to Convert Fahrenheit to Kelvin
Temperature conversions like Fahrenheit to Kelvin use specific non-linear formulas.
Formula:
K = (°F - 32) × 5/9 + 273.15Example Calculation:
Convert 10°F: (10 - 32) × 5/9 + 273.15 = 260.93K
Disclaimer: For Reference Only
These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.
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What is a Fahrenheit and a Kelvin?
Degree Fahrenheit (°F) is a unit of temperature on the Fahrenheit scale, a temperature scale developed by Daniel Gabriel Fahrenheit. On this scale, the freezing point of water is defined as 32°F and the boiling point as 212°F, placing the two points 180 degrees apart. It is primarily used in the United States and a few other countries for everyday temperature measurements.
Kelvin (symbol: K) is the base unit of thermodynamic temperature in the International System of Units (SI). It is an absolute temperature scale, meaning 0 K represents absolute zero, the theoretical lowest possible temperature where all thermal motion ceases. Unlike Celsius and Fahrenheit, Kelvin is not expressed in degrees.
Note: The Fahrenheit is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Kelvin belongs to the imperial/US customary system.
History of the Fahrenheit and Kelvin
The Fahrenheit scale was proposed in 1724 by the physicist Daniel Gabriel Fahrenheit. He initially defined 0°F based on the temperature of a brine solution (ice, water, and ammonium chloride) and set human body temperature at 96°F. Later refinements adjusted the scale so that water's freezing point was exactly 32°F and boiling point exactly 212°F.
The Kelvin scale was proposed by William Thomson, 1st Baron Kelvin, in 1848. He recognized the need for an absolute thermodynamic scale based on the principles of thermodynamics, independent of the properties of any specific substance. Absolute zero (0 K) was determined by extrapolating the behavior of ideal gases. The size of one kelvin unit is defined as the same magnitude as one degree Celsius (1 K = 1°C in terms of temperature difference).
Common Uses for degrees Fahrenheit and kelvins
Explore the typical applications for both Fahrenheit (imperial/US) and Kelvin (imperial/US) to understand their common contexts.
Common Uses for degrees Fahrenheit
- US Weather: Everyday weather reporting and forecasting in the United States and its territories.
- US Domestic: Domestic temperature settings (thermostats, ovens) in the US.
- US Medical: Medical temperature measurements in the US.
- US Culinary: Some cooking applications, particularly in recipes originating from the US.
Common Uses for kelvins
- Scientific Research: Scientific research, particularly in physics, chemistry, and thermodynamics.
- Cryogenics: Measurement of very low temperatures (cryogenics).
- Lighting & Photography: Color temperature measurement in lighting and photography.
- Astronomy: Astronomy and astrophysics for measuring celestial body temperatures.
- SI Standard: Official SI unit for temperature in scientific contexts.
Frequently Asked Questions
Questions About Fahrenheit (°F)
Why is the freezing point of water 32°F?
Fahrenheit's initial scale used different reference points. When the scale was later standardized using water, the freezing point landed at 32°F based on the original scale's divisions.
How does Fahrenheit relate to Celsius?
The relationship is linear but involves an offset. To convert Fahrenheit to Celsius, use the formula: °C = (°F - 32) * 5/9. To convert Celsius to Fahrenheit: °F = (°C * 9/5) + 32.
Where is Fahrenheit still commonly used?
The United States is the primary country that uses Fahrenheit for everyday temperature measurements. It's also used in some Caribbean countries and US territories like Puerto Rico, Guam, and the U.S. Virgin Islands. Most other countries use Celsius.
About Kelvin (K)
Why doesn't Kelvin use degrees?
Kelvin represents an absolute scale starting from zero. The term 'degree' is typically associated with scales that have arbitrary reference points (like the freezing point of water). Since Kelvin starts at the fundamental limit of temperature, the unit itself is simply 'kelvin'.
What is absolute zero?
Absolute zero (0 K, or -273.15 °C, or -459.67 °F) is the lowest theoretical temperature. At this point, particles have minimal vibrational motion, retaining only quantum mechanical zero-point energy.
How does Kelvin relate to Celsius?
The conversion is straightforward because the size of the units is the same: K = °C + 273.15. To convert Kelvin to Celsius: °C = K - 273.15. A change of 1 K is identical to a change of 1°C.