Age Calculator

How to use

1. 1Pick your date of birth. Optionally enable 'Include birth time' for hour, minute, and second precision.
2. 2Choose 'Right now (live)' for a counter that updates every second, or 'On a specific date' to see your age on a past or future day.
3. 3Read your exact age, days until next birthday, day of birth, lifetime stats, zodiac, and your age on other planets.
4. 4Use any Copy button to grab a value, or click Copy summary for a one-line summary you can paste anywhere.

About this tool

Age Calculator turns a date of birth into a complete picture of how much time has passed: your calendar-correct age in years, months, and days, plus optional hours, minutes, and seconds when you supply a birth time, with a live counter that ticks once per second on your local clock. The result panel shows the day of the week you were born, your total time alive in years (mean tropical year), months, weeks, days, hours, minutes, and seconds, the days remaining until your next birthday and the age you will turn on it, and a 'weeks remaining of 4,000' figure based on the famous reframing of an 80-year life. A lifetime body stats card uses widely cited population averages (Mayo Clinic 70 bpm midpoint heart rate, NIH 16 breaths/min, CDC 8 hours of sleep per day) to estimate total heartbeats, breaths, and sleep so far, clearly labeled as estimates. A zodiac card shows your tropical Western zodiac sign with its element, your Chinese zodiac animal anchored at the 1900 Rat year, and your birth weekday. A planet ages card divides your Earth age in days by Mercury, Venus, Mars, Jupiter, and Saturn's sidereal orbital periods (NASA fact sheet values) so you can see how old you would be on each. An 'as of' switch lets you compute your age right now (live), on a past date (how old was I when X happened), or on a future date (how old will I be on a specific day). The tool runs entirely in your browser, so the date of birth you type is never sent to a server. Useful for filling in a real exact age (years, months, days) on a form instead of guessing, planning a milestone birthday, working out how old someone will be on a wedding or graduation date, calculating a child's age in months for paediatric records, finding the day of the week you were born, comparing your age across planets for fun, or just answering 'how old am I, exactly' down to the second.

Free to use. Works in your browser. No signup, no login.