How to Use the Day of the Year Calculator
Ever wonder exactly how far into the year today is, or how many days are left until the year wraps up? This calculator tells you which day of the year (Day of Year, or DOY) any given date falls on. It is handy for tracking progress on annual goals, estimating how many days remain before a project deadline, or simply noting the day-of-year number in a planner.
The math is simple: we count the days elapsed since January 1st of that year and add 1. January 1st is day 1, and December 31st is day 365 in a regular year. In leap years, which include February 29th, the year has 366 days, so every date from March onward falls one day later in the count than it would in a non-leap year. The calculator automatically detects leap years, so the result is accurate no matter which year you enter.
Just pick a date and the result appears instantly, showing the day-of-year number, how many days remain until December 31st, and what percentage of the year has already passed. Use it to check in on New Year's resolutions, plan out the rest of the year, or track progress on any deadline.
Frequently Asked Questions
We count the days elapsed from January 1st up to the entered date and add 1. For example, December 31st is day 365 in a non-leap year.
Leap years have 366 days because of February 29th, so every date from March 1st through December 31st falls one day later in the count than in a regular year.