Anniversary Calculator

Find completed anniversary years and the next anniversary date for a relationship or milestone.

How to use anniversary calculator

  1. Enter the original milestone date
  2. Choose the date to calculate at
  3. Read completed years and time to the next anniversary

Worked example

October 14, 2020 to October 14, 2026

6 completed years; anniversary today

How the result is calculated

Completed years use calendar anniversaries, not days divided by 365. February 29 anniversaries use your selected common-year convention. Future original dates are rejected.

Inputs stay in your browser. You can use this tool without joining the waitlist or creating an account.

From a calculation to a daily glance

Keep that milestone in view.

Save your next anniversary as a named countdown in the app and choose a countdown widget style.

  1. 1Create or select your countdown in the app.
  2. 2Choose its widget assignment or a matching style.
  3. 3Add the corresponding Lock Screen widget.
Get early accessExplore widget designs

Web results do not automatically sync to the app. Setup is manual; calendar events appear through your enabled calendars.

Timer Countdown native iPhone preview
Countdown widget · example design from the app

Frequently asked questions

How does this anniversary work?
Completed years use calendar anniversaries, not days divided by 365. February 29 anniversaries use your selected common-year convention. Future original dates are rejected.
How can I use the result with Monthly Calendar Widgets?
Save your next anniversary as a named countdown in the app and choose a countdown widget style.
Do I need an account to use this tool?
No. The tool works in your browser without an account. Your inputs are not sent to our servers. Downloaded files stay on your device.

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