To convert 57°F to Celsius, you use the standard method of adjusting for the difference in the two temperature scales.
The Fahrenheit and Celsius scales measure temperature differently, with 0°C being the freezing point of water and 100°C the boiling point. In Fahrenheit, these correspond to 32°F and 212°F, respectively.
When converting, you first remove the offset of 32 (since 0°C aligns with 32°F). Then, because the Fahrenheit scale is more granular—spanning 180 degrees between freezing and boiling compared to Celsius’s 100 degrees—you divide the remaining difference by 1.8.
Using this method, 57°F is a cool and comfortable temperature that corresponds to around 13.89°C. This is typical of a pleasant spring day in many parts of the world.