Age Calculator
Find your exact age in years, months, and days based on your date of birth and any "as of" date you choose.
Your age
26y 4m 0d
9,617 days total
Formula
Age = whole years + leftover months + leftover days from DOB to the chosen date
Worked example
Born 1990-08-15, age on 2025-05-15.
- From 1990-08-15 to 2025-08-15 would be 35 years, but the as-of date is before the birthday, so it is 34 years.
- From 2024-08-15 to 2025-05-15 is 9 months.
- Final answer: 34 years, 9 months, 0 days.
Answer: 34 years, 9 months, 0 days
How it works
We start by counting full years between the two dates, then subtract one year if the birthday hasn't been reached yet in the target year. Whatever's left over is filled in with months and days.
Leap years are handled by working with real calendar dates rather than fixed-length months, so February 29 birthdays and end-of-month dates land where you'd expect.
The total days figure is the simple end-minus-start difference and is handy for milestones like "how many days have I been alive".
Common mistakes
- Picking an "age on" date that comes before the date of birth — that's flagged as an error rather than producing a negative age.
- Typing impossible dates like 2025-02-30 — the calculator rejects these instead of silently rolling them into March.
- Forgetting that a 2-month-old is roughly 60 days, not 30 — months have different lengths.
FAQ
- Does this account for leap years?
- Yes. Days are counted from real calendar dates, including February 29 in leap years.
- Can I find my age on a future date?
- Yes. Set the "Age on date" field to any date you choose, past or future.
- Why do the months and days reset around my birthday?
- Because the calculator counts complete years first. The month and day numbers measure how far you are past your most recent birthday.
- Is the answer the same as my legal age?
- In most places legal age is the number of complete years, which matches the years value shown here.
- What if I was born on February 29?
- On non-leap years your last birthday counts as February 28 for age math, so the calculator still gives you a whole number of years.