days to years
This converter makes instant conversions from days to years as time duration. To use the converter, please provide a value in the input field. The converter will begin making conversions as the values are being typed in. To add or subtract time from a date, please use our date calculator. To add, subtract, multiply, and divide time, please use our time calculator. To calculate the time between two dates, please use our days calculator.
Day and year are both units of time. In everyday life, a day or year normally refers to a calendar day or calendar year, which are the approximations of the time taken for the Earth to rotate about its own axis and to orbit around the Sun, respectively. The most widely used calendar system in the world today is the Gregorian calendar. It was first introduced in October 1852 by Pope Gregory XIII to replace the Julian calendar.
How many years in a day?
A calendar year in the Gregorian calendar, or modern calendar, consists of 365 days in a common year or 366 days in a leap year. It has a complete leap cycle of 400 years, where every 4^{th} year is a leap year except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400. Within the 400 years cycle, there are 97 leap years. Therefore, on average, there are = 365.2425 days in a calendar year. Based on this, on average, there are ≈ 0.002737907 years in a day.
How to convert days to years
Based on the definition of 365.2425 days in a calendar year on average, the day to year conversion formula is:
year = 

Thus, to convert from days to years, divide a value in days by 365.2425. For example, convert 500 days to years:
500 d = 

yr = 1.3689535 yr 