Age Calculator — Years, Months and Days
Published by H. Jhon · October 2026
Work out your exact age — in years, months and days — as of any date you choose. The calculator also shows the total number of days you've lived and how many days remain until your next birthday.
Last updated: October 2026.
How the age calculator works
How is exact age calculated?
Age is counted in completed years, months and days — you are not "one year older" until your birthday has passed. The calculator treats leap years correctly: someone born on 29 February simply has their birthday on 1 March in common years, and the day count includes the extra day of every leap year. This is why "age in total days" is always a whole number of days lived, while years-and-months depends on the calendar.
Why exact age matters
Official rules almost always use completed age, not the year of birth. A few common examples: school entry cut-off dates, applying for a provisional driving licence, minimum ages for voting and contracts, insurance brackets, and retirement milestones such as state pension age. HR and payroll systems also use completed age for things like workplace pension auto-enrolment.
If you need age at a future date — for example "how old will I be on 1 July 2030?" — enter that future date as the "age at" date and the calculator answers it directly. This is handy for retirement planning, visa applications and school admission deadlines.
Related tools
Counting is based on calendar dates, not birth time — so two people born on the same date in different time zones have the same calculated age. If you need age in months only (for example a baby's development check), the month figure above is the completed-months count.
Embed this calculator
Copy the code below to add this free calculator to your website or blog. No signup, no branding inside the tool.
The embed adapts to your page width and works on any CMS — WordPress, Squarespace, Wix, Ghost, plain HTML.
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- Enter your date of birth and the date to calculate your age on (defaults to today).
- The calculator counts full years, then months, then days — the same method official forms use.
- Leap years are handled automatically because the maths uses real calendar dates.
- You also get total days lived and a countdown to your next birthday.
Frequently asked questions
How is exact age calculated?
Age is counted in full calendar units: subtract birth date from the target date year by year, borrowing days and months as needed. This is the method used on official documents worldwide.
Does the calculator handle leap years?
Yes. Because it works with real dates rather than averages, 29 February birthdays and leap years are handled correctly.
Can I calculate age at a past or future date?
Yes — change the 'Calculate age on' field to any date. Useful for forms asking 'age as of' a specific date, or historical research.
How do I know when my next birthday is?
The calculator shows the number of days remaining until your next birthday automatically.
Estimates are for guidance only and are based on published 2026/27 rates. Always confirm with a qualified professional for financial decisions.