Age Calculator

How this age calculator works

Enter a date of birth and a reference date. The reference date starts at today, so you immediately see your current age; change it to any past or future day to find how old someone was, or will be, on that date. The result updates as soon as both dates are set — there is nothing to submit, no sign-up, and nothing to install.

Nothing is uploaded. The whole calculation runs in your browser, so the dates you enter never reach our server, are never stored, and are never logged. The only place a date is kept is in the page address, and only if you copy the link to share a particular result.

Reading the result

The headline figure is your exact age in years, months and days — the way age is normally spoken. Below it, the same span is restated as a total number of weeks and a total number of days, handy for milestones and record-keeping.

How years, months and days are counted

We count the full years from the birth date to the reference date, then the whole months since the last birthday, then the days left over. Because calendar months are different lengths, the leftover days borrow from the real length of the preceding month rather than a fixed 30. That is why the breakdown matches what a person would say by hand, and why the total-days figure is not simply the years multiplied by 365 — every leap day that fell between the two dates is counted.

The insights

• Next birthday — the number of days from the reference date to the next anniversary of the birth date.
• Birth year type — whether the year of birth was a leap year (366 days) or a standard year (365).
• Zodiac sign — the Western (tropical) sun sign for the birth month and day; for example Capricorn runs from 22 December to 19 January. The reference date does not affect it.

A note on time zones

Ages are whole-day, calendar counts, so the result is the same wherever you are — it does not shift with your time zone or with daylight saving. Two people entering the same two dates will always get the same age.

Frequently asked questions

How is age in years, months and days calculated?

We count full years from the date of birth to the reference date, then the whole months since the last birthday, then the leftover days. Because months are different lengths, the day count borrows from the actual length of the preceding month — so the result matches how people naturally say an age ("26 years, 6 months and 18 days"), not an approximation from a fixed 30-day month.

Why doesn't the total number of days equal years × 365?

Leap years add a day every four years, so a fixed 365-day year drifts. The total-days figure is the real number of calendar days between the two dates, counting every leap day that fell in between, which is why it won't match a simple multiplication.

What is the "reference date" for?

By default it's today, giving your age right now. Change it to any date — past or future — to find how old someone was, or will be, on that day: useful for eligibility dates, anniversaries, or historical ages.

Is my date of birth sent anywhere?

No. The calculation runs entirely in your browser — nothing is uploaded, stored or logged. The dates only appear in the page address if you copy the link to share a specific result.

How is the zodiac sign determined?

From the month and day of birth, using the common Western (tropical) date ranges — for example Capricorn covers 22 December to 19 January. The birth year and the reference date don't affect it.