How do I calculate my age from date of birth?

Enter your date of birth and optionally a reference date. The calculator will compute your exact age in years, months, and days, including leap years.

Can I see my age in days, weeks, and seconds?

Yes. In addition to years, months, and days, the tool shows your age in total days, weeks, hours, minutes, and seconds, plus fun milestones like your 10,000th day and 1 billion seconds.

Can I compare ages between two people?

Yes. Use the age difference section to enter two dates of birth and see who is older and by how many years, months, and days.

Age Calculator with Fun Milestones & Next Birthday Countdown

Q: Does this age calculator consider leap years?

Yes. The age calculator uses actual calendar dates, month lengths, and leap years when calculating years, months, and days.

Find your exact age in years, months, days – plus total days lived, upcoming milestones, zodiac sign, and age on other planets. Fast, free, and mobile-friendly.

Your Date of Birth

Date of birth

Calculate age as of

Include time of birth (for seconds & milestones)

Your Age

Exact age –

Decimal age –

Total days lived

–

Total weeks lived

–

Hours

–

Seconds

–

Next Birthday

–

Half Birthday

–

Perfect excuse to celebrate 🎉

Birth Facts

Born on –
Zodiac sign –
Chinese zodiac –
Birthstone –

Milestones

10,000 days old on –
20,000 days old on –
1 billion seconds old on –

Age on Other Planets

Mercury –
Venus –
Mars –
Jupiter –

Age Difference Calculator

Person A – Date of birth

Person B – Date of birth

Difference Result

Enter both dates to see who is older and by how much.

Difference –
Total days difference –
Weeks difference –

Age Calculator FAQ

How do I calculate my age?

Enter your date of birth and optionally a reference date. By default, the calculator uses today's date. Tap "Calculate Age" to see your age in years, months, and days, plus total days, weeks, and seconds lived.

Does this age calculator consider leap years?

Yes. We use actual calendar math and handle varying month lengths and leap years, so the result matches real-world age as used on legal and official documents.

Can I check my age on a past or future date?

Yes. Use the "Calculate age as of" field to pick any date. This is useful for checking how old you were (or will be) on a particular day.

What are age milestones like 10,000 days or 1 billion seconds?

These milestones show fun dates when you will reach special numbers of days or seconds lived. They're great for birthday surprises, social media posts, and celebrations.