Enter the birth date
Pick the date of birth from the date field.
Calculators
Age Calculator
Free online exact age calculator
Enter the values
Local processingLeave the second date empty to calculate the age today.
Result
The result will appear here after you run the tool.
Press Ctrl or Command and Enter to run the tool.
About this tool
About this tool
Age Calculator computes calendar-accurate age in years, months, and days between a birth date and a reference date using real month lengths, including leap years. It also reports total days, months, and weeks, plus the countdown to the next birthday. Everything is calculated locally in your browser.
Find out exactly how old someone is, down to the day. Enter a date of birth and optionally a reference date, and the calculator reports the age in years, months, and days, the total days lived, total months and weeks, and how many days remain until the next birthday. Leave the reference date empty to use today.
Built for daily work
- Verify age for forms, applications, and eligibility checks.
- Plan birthday celebrations with an exact countdown.
- Calculate age at a specific past date for records.
- Work out duration since a milestone for a timeline.
How to use this tool
How to use this tool
Set the reference date
Leave it empty for today, or choose a specific date such as a milestone or an event.
Read the breakdown
The result shows the age in years, months, and days plus totals and the next birthday countdown.
Key features
Key features
Calendar-accurate months
The age accounts for real month lengths and leap years, so month counts match how people describe age.
Any reference date
Calculate age on a past or future date, not just today, for milestones and paperwork.
Total durations
Total days, months, and weeks give a second perspective beyond the year-month-day answer.
Next birthday countdown
See exactly how many days remain until the next birthday, including leap day handling.
Practical use cases
Practical use cases
- Verify age for forms, applications, and eligibility checks.
- Plan birthday celebrations with an exact countdown.
- Calculate age at a specific past date for records.
- Work out duration since a milestone for a timeline.
- Double-check ages for insurance or membership documents.
Private by default
For local tools, input is processed in your browser and is not sent to application analytics.
Data processing noticeTechnical details
Technical details
ProcessingLocal browser processing
InputBirth date and optional reference date
OutputYears, months, days, totals, next birthday
Calendar rulesReal month lengths and leap years
Limitations and important notes
Limitations and important notes
- Age is measured in whole calendar days; time of day is not considered.
- Legal age definitions vary by jurisdiction and context.
- Dates before the modern Gregorian calendar adoption may not match historical records.
Frequently asked questions
Frequently asked questions
The tool counts complete calendar months between the dates, adjusting for shorter months, then counts remaining days. This matches how ages are usually spoken.
A February 29 birthday is handled with the nearest valid date in non-leap years, so the countdown never breaks.
Yes. Enter any reference date; the calculator reports the age that person will have reached by then.
Only when you leave the reference date empty, to define "today". You can always set a fixed date instead.
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