Age calculator: how old are you, exactly?
Enter your date of birth and this free online age calculator finds your exact age — as of today or any date — down to the second, plus upcoming milestones worth celebrating.
Weeks
Days
Hours
Minutes
Seconds
Leap years lived
Your years, ring by ring
Each ring is one year of your life — dashed teal rings mark leap years. The coral arc fills in as your current year progresses toward your next birthday.
Upcoming milestones
About this age calculator
This age calculator works out your exact age in years, months and days, plus running totals in weeks, hours, minutes and seconds — updated live as you watch. It's built to handle the messy parts of the calendar so you don't have to.
Age calculator by date of birth, on any date
This is a date of birth calculator at heart, but it also handles the less common cases people search for. Switch to "as of a date" mode and you can calculate age on any date in the past or future — useful for checking eligibility cutoffs, filling out forms that ask for age as of a specific day, or working out how old someone will be for a future event. Leave it on "as of today" for a straightforward age calculator for today, recalculating the exact age the moment you load the page.
Age calculator for babies, and corrected age
Because the tool tracks weeks and days as precisely as years, it doubles as an age calculator for a baby — parents can see a newborn's age in weeks and days rather than waiting for the first birthday for a meaningful number. There's also a dedicated corrected age calculator for babies born prematurely: toggle it on, add the original due date, and it shows the baby's corrected (adjusted) age alongside their regular age — which is what most growth charts and developmental milestones actually reference for preemies.
Precise down to the second
Every result is built from the same underlying calculation, so the numbers stay consistent with each other: total weeks, days, hours, minutes and seconds are all derived from the real elapsed time between the date of birth and the reference date. An optional birth time sharpens the hour-level totals even further.
Korean age, zodiac sign and Chinese zodiac
Alongside the core numbers, this age calculator online adds a few cultural touches: Korean age, Western zodiac sign, and an approximate Chinese zodiac animal based on birth year. A tree-ring visualization shows each year of life at a glance, and you can download or share the results as an image once you're done.
Free, instant, and private
There's no sign-up, no app to install, and no limit on how many times you use it — check your own age, a baby's age, or someone else's for a form that asks for their age as of a given date, as often as you like.
Frequently asked questions
What is my age calculator?
It's a free online age calculator that works out exactly how old you are (or how old someone else is) from a date of birth. Enter the date and it instantly shows your age in years, months and days, plus totals in weeks, hours, minutes and seconds, upcoming birthday milestones, and cultural extras like your Korean age and zodiac sign — all calculated in your browser, with nothing sent to a server.
How old am I?
Enter your date of birth above and this age calculator answers that instantly — your exact age in years, months and days, updated live down to the second. You can also check how old you were, or will be, on any other date by switching to "as of a date" mode instead of today.
How is my age calculated?
We count full calendar years, months and days between your date of birth and the reference date. A 'month' is complete once you reach the same day-of-month again (or the last day of a shorter month — for example, one month after January 31st lands on February 28th or 29th). Totals in weeks, days, hours, minutes and seconds are calculated separately from the exact elapsed time, so they stay accurate even across leap years and daylight saving changes.
What if I was born on February 29th?
In years that aren't leap years, we treat February 28th as your birthday for countdown and milestone purposes. Your leap-year count still only counts the actual February 29ths you've lived through.
Why might 'total hours' not exactly equal 'total days' times 24?
If your time zone observes Daylight Saving Time, this is already handled automatically: twice a year, clocks move forward or back, making some days 23 or 25 hours long. Our totals reflect that real elapsed time rather than a flat 24-hour multiplication, so this is expected and correct, not a rounding error.
Do you account for the exact time I was born?
Only if you tell us. The 'Birth time' field is optional — if you fill it in, we use it to sharpen your hour/minute/second totals; if you leave it blank, we assume midnight on your date of birth, which can make your true age differ from our result by up to a day at the hour/minute level.
What is "Korean age", and how accurate are the zodiac signs?
Korean age is the traditional counting age used across East Asia: you're age 1 at birth, and everyone ages up together on January 1st rather than on their birthday (South Korea's legal age system switched to the international standard in June 2023, but counting age is still common culturally). Your Western zodiac sign is exact, based on your birth month and day. Your Chinese zodiac animal is approximated from your Gregorian birth year — if you were born in January or February, close to Lunar New Year, your actual animal year could be the one before it.
Is my data sent to a server?
No. Every calculation happens in your browser using JavaScript. Nothing about your date of birth is transmitted, logged, or stored — unless you choose to share a link, an image, or a calendar file, which only contain what you explicitly generate.