Age Calculator

Exact age, days between dates, add or subtract days — all in your browser.

100% in your browser. Nothing uploaded.

Accepts a date picker or plain text like 1990-03-15.

For an hour-precise reading. Defaults to midnight.

Sponsor slot age-result

Life-event inventory (insurance, retirement, life-stage products).

A simple age calculator that respects your time

Discover your precise age with our easy-to-use online age calculator. Simply enter your birth date and time to see your age in years, months, weeks, days, hours, and even seconds. Need to plan an event? Use our date duration feature to find the exact number of days between any two dates, or calculate a future date by adding or subtracting days from today. Our privacy-first approach means your dates never leave your device, making it the safest way to track your milestones.

How to use it

  1. Pick a tab. Age from DOB takes a date of birth (and optional birth time) and reports your exact age.
  2. Days between dates takes any two dates and counts the calendar days between them.
  3. Add or subtract days takes a start date and a day count (negative to go backwards) and gives you the resulting date.
  4. Hit Copy share link — every input is stored in the URL hash, so you can paste it into a chat without us ever seeing it.

How the math works

Birthday gifts & life-event picks

Amazon Associates strip ships once the account is approved. The slot keeps its layout so it can be filled without re-deploying the site.

FAQ

How exact is the age calculation?

We compute calendar age the way humans count it: full years first, then full months, then full days, then remaining hours. A person born on Feb 29 is reported as having a birthday on Feb 28 in non-leap years, matching most legal and bureaucratic conventions.

Does it handle leap years and daylight-saving time?

Yes. The day/month/year math uses calendar arithmetic that respects leap years from 1900 through 2100. Hour math uses UTC under the hood so DST transitions never add or drop an hour in the result.

Can I share my result?

Yes. Every input is stored in the URL fragment (the part after #), so copying the address bar gives someone the same dates without us ever seeing them. Nothing is sent to a server.

What does “add 7 days” actually mean?

Seven 24-hour periods from the start date, in your local time zone. We deliberately avoid the “same wall-clock time on the date 7 days later” interpretation so the answer never silently changes across a DST boundary.

Does this work offline?

Yes, after the first visit. The page and its scripts are static and get cached by your browser; the calculator runs entirely client-side with no API calls.