Age Calculator — How Old Am I?
Work out your exact age from your date of birth in seconds. This age calculator shows your age in years, months and days, plus your total age in months, weeks, days and hours, the day of the week you were born, and a live countdown to your next birthday. Switch dates to Buddhist era (พ.ศ.) if you need them. Everything runs in your browser, with no sign-up and nothing sent to a server.
Pick the day you were born.
Leave blank to use today. Pick a date to see your age on that day.
Adds 543 years to the shown dates. The age itself does not change.
Your age will appear here
Enter your date of birth to see your exact age and next birthday.
Years
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Months
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Days
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Total age in each unit
| Unit | Total |
|---|
Each row shows your whole age expressed only in that single unit.
Birthday details
How to use
- Enter your date of birth using the date picker.
- Leave the second field blank to use today, or pick any date to see your age on that day.
- Read your exact age in years, months and days at the top of the results.
- Check the totals table for your age in whole months, weeks, days and hours.
- See the day you were born and how long until your next birthday, then Copy summary to share it.
Features
- Exact age in years, months and days from any date of birth
- Total age in months, weeks, days and hours
- Day of the week you were born
- Live countdown and days until your next birthday
- Buddhist era (พ.ศ.) toggle for all shown dates
- 100% in-browser — your date of birth never leaves your device
Frequently asked questions
How do I calculate my exact age?
Enter your date of birth and the tool counts the full years, months and days up to today. For example, someone born on 15 March 2000 is 26 years, 4 months and 4 days old on 19 July 2026, calculated using the real length of each month.
How does the age calculator count months and days?
It counts complete calendar months and then the remaining days, using the actual number of days in each month. This matches how age is normally stated, rather than assuming every month has 30 days.
Can I calculate my age on a future or past date?
Yes. Fill in the "Age at date" field with any date and the tool shows how old you were, or will be, on that day. Leave it blank to use today automatically.
What is the Buddhist era (พ.ศ.) toggle?
Thailand commonly uses the Buddhist calendar, which is 543 years ahead of the Gregorian year. Turning the toggle on shows every date in Buddhist era format. Your calculated age stays exactly the same.
Is this age calculator free and private?
Yes. It is completely free, needs no sign-up, and runs entirely in your browser. Your date of birth is never uploaded or stored anywhere.