What does this tool do?
Adding years preserves the month and day, except for 29 February, which has no equivalent in common years. Choose whether that anniversary should land on 28 February or 1 March.
The Formula
Result date = start date with the year changed by NFrequently Asked Questions
What happens to a 29 February date?
In a common year there is no 29 February. The calculator uses 28 February by default, or 1 March if you select that option.
Why is the day count not exactly 365 times the years?
Leap years add an extra day and month lengths vary. The result matches the same calendar date, so the number of elapsed days depends on the interval.