Age Calculator
Calculate age in years, months and days from a birth date to a selected date.
Calculator
Results
How it works
Calculate age in years, months and days from a birth date to a selected date.
Example
| Example | Result |
|---|---|
| May 20, 1990 to Sep 19, 2026 | 36 years, 3 months, 30 days. |
Important notes
- Calendar calculations use Gregorian calendar rules.
- Business-day calculations exclude Saturday and Sunday unless stated otherwise.
- Time-zone calculations depend on the browser's IANA time-zone data.
- For planning purposes, verify dates and times when a contractual or legal deadline is involved.
Frequently Asked Questions
Does the calculator use today automatically?
This version lets you choose the age-on date for reproducible results.
Does it handle leap-day birthdays?
Yes, using JavaScript calendar rules; February 29 anniversaries require interpretation in non-leap years.
How to use this calculator
What to enter
Enter or select the following as requested: Date of birth; Age on. Follow the units, valid ranges, examples, and options displayed beside each field.
What the result means
The date or duration result is calculated from the entered dates, times, calendar rules, and exclusions. Check inclusive versus exclusive counting, time zone, daylight-saving changes, and whether weekends or holidays are excluded.
When to use it
Use this to plan a date, measure elapsed time, or estimate a deadline. Verify the relevant calendar, location, and legal or workplace rules when they affect the answer.