Convert Fahrenheit to Kelvin

The Fahrenheit (symbol: °F) is a unit of temperature. A temperature scale introduced by Polish-German physicist Daniel Gabriel Fahrenheit in 1724 — on which water freezes at exactly 32 °F and boils at exactly 212 °F under standard atmospheric pressure (101.325 kPa). The 180-degree span between freezing and boiling is divided into smaller intervals than Celsius (1 °C = 9/5 °F), giving finer resolution in everyday weather conversation. Fahrenheit remains the dominant temperature scale in the United States, Belize, and the Cayman Islands for: weather reporting (NOAA / NWS US forecasts in °F; typical US summer high 85-100 °F; winter low 10-32 °F across temperate latitudes); cooking and oven temperatures per US-edition cookbooks + USDA FSIS food-safety thresholds (safe meat cooking 145 °F poultry breast, 165 °F poultry whole, 145 °F pork, 145 °F beef medium-rare); HVAC thermostat settings (typical 68-72 °F heating, 72-78 °F cooling per ASHRAE 55 occupant-comfort thermal envelope); pool and spa water (typical 78-82 °F pool, 100-104 °F spa); refrigerator/freezer per US FDA (refrigerator ≤40 °F, freezer ≤0 °F). The Fahrenheit scale's smaller degree interval is sometimes argued to be a feature for human-comfort discussion ('72 °F vs 73 °F is a noticeable difference').

It belongs to the imperial measurement system.

Fahrenheit are commonly used in weather forecasting, cooking, scientific experiments, and HVAC.

The Kelvin (symbol: K) is a unit of temperature. The SI base unit of temperature per ISO 80000-5 §5-1, measured on an absolute scale where 0 K is absolute zero — the theoretical point at which all classical thermal motion stops (zero-point quantum motion remains). Named after Belfast-born British physicist William Thomson, 1st Baron Kelvin (1824-1907), whose 1848 paper 'On an Absolute Thermometric Scale' established the absolute-temperature concept. Redefined in 2019 BIPM SI revision by fixing the Boltzmann constant k_B = 1.380649 × 10⁻²³ J/K exactly. Kelvin shares its degree interval with Celsius (1 K = 1 °C, but offset by 273.15: 0 °C = 273.15 K), so conversion is a straight addition. Scientific publications, thermodynamic state-function math (entropy ds, free energy dG = dH - T·dS — requires absolute temperature), cryogenic physics (liquid helium boils at 4.2 K, liquid nitrogen at 77.4 K, dry ice CO₂ sublimes at 195 K), color temperature in photography and lighting (incandescent 2,700-3,000 K, daylight 5,500-6,500 K, blue sky 10,000-15,000 K), stellar surface temperatures (Sun 5,778 K; Sirius 9,940 K; Betelgeuse 3,500 K), and plasma physics (fusion plasma 10⁸ K) all use kelvin because absolute-zero-referenced math stays dimensionally clean.

It belongs to the metric measurement system.

Kelvin are commonly used in weather forecasting, cooking, scientific experiments, and HVAC.