Worked example. Change the dates to calculate your own.
December 25, 2026
- Next date
- 2026-12-25
- Age on that date
- 31
- Original date
- December 25, 1995
Finds the next annual birthday on or after the reference date and the age at that date. February 29 follows your selected celebration policy. This is a personal calendar calculation, not a legal age rule.
Dates stay in this page. No account, uploads or server calculation.
How this calculation works
The tool finds the next birthday on or after the reference date. It shows days remaining and age on that date. For February 29, choose February 28, March 1, or the next leap year.
A worked example
A birth date of December 25, 1995 and reference date of October 1, 2026 gives 85 days until December 25, 2026. The person reaches 31 on that date. For February 29, choose February 28, March 1 or the next actual leap-day occurrence.
Choose the recurrence policy rather than hiding it
The next occurrence can be the reference date itself. February 29 has three explicit choices.
| Original and reference | Personal calendar result |
|---|---|
| December 25, 1995. Reference October 1, 2026. | 85 days to December 25, 2026. Age on that date is 31. |
| December 25, 1995. Reference December 25, 2026. | 0 days. The next occurrence is today. |
| February 29, 2000. Reference February 1, 2027. Choose February 28. | 27 days to February 28, 2027. |
| Same dates. Choose March 1. | 28 days to March 1, 2027. |
Enter your dates
Enter the birth date and reference date, choose the February 29 rule if needed, then Calculate. Use today's date to check the next birthday now. This is a personal planning calculation.
Create a countdown for the next birthday
Add the birthday to Daymark with a photo and an early gift reminder. Keep a separate countdown if the party falls on another date.
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