Enter the start date and the number of years into the calculator to determine the anniversary date; this calculator can also evaluate any of the variables given the others are known.

Anniversary Calculator

Enter any 2 values to calculate the missing variable

Related Calculators

Anniversary Formula

The following formula is used to calculate the anniversary date (by adding calendar years to the start date):

AD = SD + Y

Variables:

  • AD is the anniversary date
  • SD is the start date
  • Y is the number of years

To calculate the anniversary date, add the number of years to the start date while keeping the same month and day when possible. If the start date is February 29 and the target year is not a leap year, this calculator shifts the result to March 1.

What is an Anniversary?

An anniversary is a date that marks a significant event or milestone that occurred in a previous year, and is traditionally celebrated or acknowledged each year on the same date. The term is most commonly used to denote the years since the occurrence of a wedding or the beginning of a romantic relationship, but it can also be used to commemorate other significant events such as the founding of a company, the end of a war, or the death of a loved one.

Anniversaries are often celebrated with special activities, gifts, or rituals that reflect the importance of the event and the passage of time. For example, wedding anniversaries are often associated with specific gifts like paper for the first year, silver for the 25th year, and gold for the 50th year.

How to Calculate an Anniversary Date?

The following steps outline how to calculate an anniversary date (or the missing value) using the formula above.

  1. Enter any two values: Start Date (SD), Number of Years (Y), and Anniversary Date (AD).
  2. If AD is missing, add Y calendar years to SD to get the anniversary date.
  3. If SD is missing, subtract Y calendar years from AD to get the start date.
  4. If Y is missing, compute the number of full years between SD and AD (subtract 1 if the anniversary month/day is earlier than the start month/day within the ending year).

Example Problem:

Use the following variables as an example problem to test your knowledge.

Start date (SD) = 2018-06-15

Number of years (Y) = 5

Anniversary date (AD) = 2023-06-15