How old am I, and other facts about my birthday
Enter your date of birth
—years old
—
—
—
Type a name above
What this actually works out
Most age calculators stop at a number. This one starts there and keeps going: your age in years, months, days, hours, minutes and seconds, ticking live, and then about a hundred and forty other things your date of birth quietly determines.
Everything is worked out in your browser
Nothing you type is sent anywhere. There is no account, no tracking of your birthday, and no server doing the sums — the whole calculation happens on your own device, which is also why it is instant.
Where the numbers come from
The dog-year conversion uses the 2019 UCSD epigenetic study rather than the old “multiply by seven” rule, which was invented in the 1950s and has no science behind it. Moon phases use the standard synodic-month calculation. Planet ages use NASA's published orbital periods. Population, inflation and CO₂ come from published figures. Anything that is a population average rather than an exact fact is labelled est so you always know which is which.
Know your birth time?
Most people don't, so the clock counts from midnight by default. If you do know it — it is on your birth certificate — you can add it, and every figure becomes exact rather than approximate.