How exact is the age calculation?

Down to the second. The calculator uses the same calendar arithmetic that date libraries use (accounting for month lengths, leap years, leap seconds in the abstract sense — wall-clock seconds — but not leap-second adjustments).

Why does my age in months not match (years × 12 + months)?

Because months have different lengths. Going from Jan 31 to Feb 28 is "1 month" by calendar convention but only 28 days. The calculator follows the standard "calendar months" definition — the month component is incremented when the day-of-month is reached or passed, just like birthdays work in the real world.

What if I was born on February 29?

Treats Feb 28 as the birthday in non-leap years. This is the legal default in most US states and similar in many other jurisdictions. Some (Hong Kong, Taiwan) use March 1 instead — the tool offers both options under settings.

Can I calculate age between two arbitrary dates?

Yes — enter both dates. The second defaults to today but you can set any past or future date.

Are my heartbeats and breaths accurate?

They're very rough estimates using average resting baselines (~70 bpm, ~16 breaths/min). Your actual lifetime totals depend on activity, age, fitness — the numbers are for fun, not medical accuracy.

Does it work for historical figures?

Yes — enter any birthdate; the calculator handles dates from year 1 onwards. Useful for \"How old would Beethoven be today?\" trivia.

Age Calculator

Exact age + countdown to next birthday

Calculators

Age Calculator

Exact age + countdown to next birthday

Date of birth

About this tool

Find out exactly how old you are — down to the year, month, day, hour, minute and second — and see a live countdown to your next birthday. Beyond the basics, this page also tells you the day of the week you were born, your zodiac sign, your Chinese zodiac, your birthstone, and a few fun life-stats: how many heartbeats and breaths you have taken, days you have slept, and orbits you have made around the Sun. Pick your date, share the link with friends, and enjoy a confetti burst if today happens to be your birthday.

How to use

1 Pick your date of birth using the date picker.
2 See your exact age in years, months and days.
3 Watch the live countdown to your next birthday.
4 Read your day of the week, zodiac, Chinese zodiac and birthstone.
5 Tap Share to copy a link with your date pre-filled — or use your phone’s native share sheet.

Examples

Born 12 Aug 1973	About 52 years 4 months — 19,143 days alive — Leo · Ox · Peridot
Born 1 Jan 2000	Capricorn · Dragon · Garnet — born on a Saturday
Born today	0 days — Happy birthday! 🎉

Frequently asked questions

It compares your date of birth to the current date in your browser to compute exact years, months and days. The countdown ticks every second based on your local clock.

Date math is sensitive to time zones and to whether the count includes the start day. We use your browser’s local time and exclude the birth day itself when reporting completed days.

We use the standard tropical zodiac dates (e.g. Leo: 23 Jul – 22 Aug). Some sources publish slightly different cusp dates; if your birthday falls on a cusp, treat it as informational rather than authoritative.

It is approximate — the Lunar New Year falls between late January and mid-February each year, so people born in those weeks can be on the boundary of two animals. We map by Gregorian year for simplicity.

They use rough averages: 70 beats per minute, 16 breaths per minute, 8 hours of sleep per day, and a 29.5-day lunar cycle. Treat the numbers as fun illustrations, not medical or astronomical truth.

Yes — the URL contains your selected date as a ?dob=YYYY-MM-DD parameter. Anyone who opens it will see the calculator pre-filled to that date.

A small open-source library called canvas-confetti, loaded on demand. It only fires when today’s date matches your birth month and day.

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Age Calculator

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