Age Calculator
Work out an exact age in years, months and days, plus total weeks, days and the next birthday.
Your details
Defaults to a fixed date so results are reproducible
This calculator runs entirely on your device. Nothing you enter is uploaded, stored, or sold. How this works
Age
36 years, 2 months, 14 days
As of Saturday, August 29, 2026
Includes your inputs, the full breakdown, and every row of the table.
Age in years
36
Total months
434
Total days
13,224
Next birthday in
290 days
- Date of birth
- Friday, June 15, 1990
- Born on a
- Friday
- Reference date
- Saturday, August 29, 2026
- Exact age
- 36y 2m 14d
- Total weeks
- 1,889
- Next birthday
- Tuesday, June 15, 2027
| Unit | Value |
|---|---|
| Years | 36.21 |
| Months | 434 |
| Weeks | 1,889 |
| Days | 13,224 |
| Hours | 317,376 |
| Minutes | 19,042,560 |
What this means
- Age is counted the way people actually use it: you turn a year older on your birthday, not after a fixed number of days.
- Someone born on 29 February has a birthday only in leap years. Most jurisdictions treat 1 March as the legal birthday in other years, though a few use 28 February.
How the age calculation works
Calculating age precisely requires calendar awareness rather than arithmetic on day counts. Months have different lengths and leap years insert an extra day, so dividing total days by 365 gives an answer that drifts — by a full day every four years, and more for older people. The correct approach borrows from the previous month when the day of the month has not yet been reached, which is exactly how you would count it manually.
This matters more than it sounds for anything with a legal or medical threshold. Eligibility for benefits, insurance bands, age of majority and paediatric dosing all depend on an exact age rather than an approximate one, and being a day out at a boundary changes the answer entirely.
Frequently asked questions
Why not just divide the number of days by 365?
Because leap years make it drift. Over forty years that approximation is off by around ten days, which is enough to put someone on the wrong side of a birthday. Counting calendar years and then months and days is both more accurate and closer to how people actually think about age.
How is age handled for someone born on 29 February?
They have a genuine birthday only every four years. Most legal systems treat 1 March as the operative date in non-leap years for reaching an age threshold, though a minority use 28 February. This calculator counts the calendar difference, which lands on 1 March.
Does this account for time zones?
It deliberately ignores them by treating every date as a whole day in UTC. That avoids the classic bug where a birthday appears to shift by a day depending on the viewer's location, and it matches how dates of birth are recorded on documents.
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Disclaimer. This calculator is provided for general information and educational purposes only and does not constitute financial, tax, legal, medical, or engineering advice. Results are estimates based on the inputs you provide and the assumptions described above. Confirm any figure with a qualified professional before acting on it.