Online Tool Store
Anniversary Calculator
Track years and days since any start date, see your next anniversary countdown, and get a full list of year and day-count milestone dates. Runs entirely in your browser.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
Example shown - replace with your own date.
Years together
Total days
Next anniversary
Milestone dates
How the anniversary calculator works
- Enter the start date you want to track.
- The tool calculates full years elapsed, total days, and the date of your next anniversary.
- It also lists year- and day-count milestones, marking which ones you've already reached.
The method
Years together is a calendar count: it compares today's date to the anniversary date in the current year, subtracting one year if that anniversary hasn't happened yet this year. Milestone dates are computed by adding whole years (for year milestones) or a fixed number of days (for day-count milestones) to the original start date.
FAQ
What milestones does the calculator show?
Common year milestones (1, 5, 10, 15, 20, 25, 30, 40, 50 years) and day-count milestones (100, 1,000, 5,000, and 10,000 days), sorted chronologically with reached ones marked.
Can I use this for anniversaries other than weddings?
Yes. Any recurring start date works - work anniversaries, relationship start dates, sobriety dates, or company founding dates.
How is the next anniversary date calculated on a leap-year birthday?
If the start date is February 29 and the anniversary year is not a leap year, the calculator uses February 28 for that year instead.
Is my date saved anywhere?
No. The date you enter stays in your browser tab and is never uploaded or stored.
How we compare
| Feature | Online Tool Store | timeanddate.com | Calculator.net |
|---|---|---|---|
| Milestone list (years and day counts) in one view | ✓ | ✗ | ✗ |
| Updates instantly as you change the date | ✓ | Calculate button | Calculate button |
| Date stays in this browser tab | ✓ | Not stated | Not stated |
For a full milestone list alongside your next anniversary, not just a single date, Anniversary Calculator gives you more at a glance.