Réaumur to Fahrenheit Converter

Réaumur (°Ré or °R) is a temperature scale where 0°Ré is the freezing point of water and 80°Ré is the boiling point of water at standard atmospheric pressure. Each degree Réaumur equals 1.25 degrees Celsius.

The Réaumur scale was developed by French scientist René Antoine Ferchault de Réaumur in 1730. He chose 80 degrees between the freezing and boiling points of water because his alcohol-based thermometer expanded by 80 parts per 1000 when heated from freezing to boiling water.

The Réaumur scale is largely obsolete and rarely used today. It may occasionally appear in historical scientific documents, some traditional European recipes (particularly in Germany and Russia), and certain specialized industrial applications. Most modern applications have switched to Celsius or Fahrenheit.

Fahrenheit (°F) is a temperature scale where 32°F is the freezing point of water and 212°F is the boiling point of water at standard atmospheric pressure. The scale uses 180 degrees between these two reference points.

The Fahrenheit scale was developed by German physicist Daniel Gabriel Fahrenheit in 1724. He originally set 0°F as the temperature of a mixture of ice, water, and ammonium chloride, and 96°F as human body temperature. The scale was later refined to use water's freezing and boiling points as reference.

Fahrenheit is primarily used in the United States, Belize, and a few Caribbean nations for weather reporting, cooking, and everyday temperature measurements. It remains the standard for medical thermometers, household thermostats, and weather forecasts in these countries, though scientific applications typically use Celsius or Kelvin.