General Calculator
DOB Calculator
Switch between finding date of birth from age and calculating exact age from date of birth, with next birthday and total days-lived context.
What this DOB calculator does
Use Age from DOB mode to calculate exact age from a birth date and reference date. Use DOB from age mode to estimate a date of birth from years, months, and days.
How to calculate age from date of birth
Enter the birth date and the date you want to measure from, then calculate. The result adds next-birthday context and total days lived so you can check the calendar math at a glance.
Reference-date note
Age depends on the reference date. For a current age, use today's date; for an official form or historical record, use the exact date requested by that form.
Frequently Asked Questions
What does a DOB calculator do?
It calculates exact age from a date of birth or estimates date of birth from age.
Can it calculate years, months, and days?
Yes. Enter a birth date and reference date to calculate the detailed age difference.
Can I estimate DOB from age?
Yes. Switch to DOB from age mode and enter years, plus any extra months or days.