Does this predict how long I will live?
No. The reference age is an adjustable illustration. No medical, demographic or personal data is used to calculate a lifespan.
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THE CALENDAR / HOW IT WORKS
How the life calendar works
The squares help you explore calendar time. They do not estimate anyone’s lifespan.
1. Choose a birthday
Your birth date is the start of the timeline. The preview uses an example date until you enter yours.
2. Set an illustrative reference age
This changes only how many age-years are drawn. It is not a prediction or medical estimate.
3. Explore years, weeks and days
Years run from birthday to birthday. Weeks are consecutive seven-day periods from birth. Days represent each actual calendar date in one selected age-year.
A worked calendar example
The period from January 1, 2000 to January 1, 2001 lasted 366 days. That equals 52 complete weeks and 2 additional days. The following year lasted 365 days, or 52 weeks and 1 day.
366 = 52 × 7 + 2 365 = 52 × 7 + 1Common questions
Are there exactly 52 weeks in every age-year?
No. Most age-years contain 365 calendar days and some contain 366. A seven-day week may cross an anniversary. Week cells are grouped by the age-year containing their start date.
What happens if I was born on February 29?
In non-leap years the calendar uses February 28 as the anniversary for display. Different legal contexts may use different birthday rules.
Can daylight saving time change the day count?
No. The visualization uses UTC calendar dates for day differences, so seasonal clock changes do not create extra or missing calendar days.
PRACTICAL GUIDE
Read the Life in Weeks guide Understand the calendar
Why weeks do not line up perfectly with age-years—and how leap days are handled.
