What is a life milestone?
A life milestone is a meaningful threshold measured from a starting date. Traditional milestones use whole ages—18, 21, 30, 40 or 100. A life-date milestone can also be 10,000 days old, 1,000 weeks alive, 500 months, a half birthday or a round number of minutes.
These dates are not more important than birthdays. They are a playful second calendar: a reason to notice time on a day that would otherwise look ordinary.
How to calculate when you will be 10,000 days old
Add 10,000 calendar days to the date of birth. Do not convert 10,000 days to years and add an approximate number of years, because leap days shift the exact date. For a next rolling milestone, first find total days lived, round up to the next thousand and add the difference to today.
Milestones worth tracking
- 1,000-day intervals: frequent enough to be fun, rare enough to feel distinct.
- 5,000, 10,000, 20,000 and 25,000 days: highly recognisable round-day landmarks.
- 500 or 1,000 weeks: good for children, adults and long relationships.
- 100, 250, 500 and 1,000 months: a different perspective on long lives.
- 10, 25 and 50 million minutes: dramatic numbers with surprisingly human dates.
- Half birthdays: useful for children, summer/winter celebrations and simple fun.
- Pet-year birthdays: milestones based on the app's supported pet-age estimates.

Track milestones automatically in LifeDates
Add a person or pet and LifeDates calculates an upcoming timeline from the date of birth. The Today screen surfaces what comes next; the profile shows the longer sequence. Premium unlocks advanced milestone timelines and reminders so a 10,000-day date does not disappear into the calendar.
- Add the person, pet or your own profile.
- Open the profile and scroll to Upcoming timeline.
- Select a milestone to see its date and distance.
- Turn on milestone reminders if you want an alert before it arrives.
- Use a share card when the day is worth celebrating with someone else.
Life milestone questions
What age is 20,000 days?
Roughly 54 years and 9 months, but use the full date of birth for the exact calendar age and date.
Are milestone calculations private?
LifeDates calculates saved timelines from data stored locally on the iPhone. No account is required.
Can I track relationship milestones?
Important Dates can represent anniversaries, adoption days and other recurring dates. Use the right starting date for the story you want to track.
There is always another date worth noticing.
Download LifeDates and find the milestone hiding between the birthdays.
Download on theApp Store