Thankfully, Reddit user quaxon shared a dead-simple method for converting between Fahrenheit and Celsius in your head with no need for a calculator.

When converting Celsius to Fahrenheit, the formula is: (°C * 1.8) + 32 = °F. You multiply 1.8 to the number of degrees Celsius, then add that number to 32. There are tricks that will help you ...

Most countries moved to Celsius in 1960 — it’s easier for calculations, because it uses 0 degrees as the freezing point of water and 100 degrees as the boiling point. Fahrenheit, in contrast ...