Date of Birth Calculator
Calculate your age from your date of birth. Enter your DOB and get your exact age in years, months, days, hours, minutes, and seconds — all updated in real time.
About Date of Birth Calculator
A date of birth calculator is a simple online tool that computes your age from your date of birth. By entering your DOB, the calculator instantly determines how many years, months, days, hours, minutes, and seconds have passed since you were born.
Our age from date of birth tool does all the hard work of accounting for leap years, varying month lengths, and time zone differences. All calculations happen entirely in your browser — your date of birth is never sent to any server.
Use this tool to calculate your exact age in various units, track upcoming birthday milestones, or simply satisfy your curiosity. The calculator updates results as you type, with no button clicking required.
Frequently Asked Questions
How do you calculate age from date of birth?
Subtract your birth year from the current year, then check whether your birthday has already happened this year. If not, subtract 1 from the year count. Our date of birth calculator does all the calendar math automatically, accounting for leap years and varying month lengths — just enter your DOB and get instant results.
How many days old am I?
Enter your date of birth into our calculator to see the total number of days you have been alive. This includes all leap days (February 29) that have occurred since your birth. The calculator also breaks this down into hours, minutes, and seconds for a complete picture of your age.
Do leap years affect age calculation?
Yes, but our calculator handles them automatically. Leap years add an extra day every 4 years (with century-year exceptions). When computing total days lived, our tool correctly includes or excludes February 29 depending on the years in your date range.
What is my exact age in months?
Your age in months is calculated by multiplying complete years by 12 and adding any remaining months since your last birthday. Our DOB calculator displays this automatically alongside your age in years, days, hours, minutes, and seconds.
Is my date of birth stored or shared?
No. All calculations happen entirely in your browser using client-side JavaScript. Your date of birth is never sent to any server, stored, or shared with third parties. Your privacy is guaranteed.