Work out an exact age in years, months and days, the time between any two dates, or the gap between two birthdays. Everything is calculated in your browser — no date you type is sent anywhere, and there is nothing to sign up for.
Calendar dates are calculated in UTC. Month-end anniversaries use the last available day, including 28 February for a leap-day birthday in a common year. This is a calculation convention, not a legal age determination. No date is uploaded.
This tool counts completed calendar months, splits them into years and months, then counts the remaining days. If the original day does not exist in the destination month, the anniversary is clamped to that month’s last day.
That convention makes 31 January to 28 February 2025 one month. In a leap year, 31 January to 28 February is 28 days because the month-end anniversary is 29 February. The total-days figure is elapsed calendar days; the start date is not counted twice.
| From | To | Result |
|---|---|---|
| 31 Jan 2025 | 28 Feb 2025 | 0 years, 1 month, 0 days |
| 31 Jan 2024 | 28 Feb 2024 | 0 years, 0 months, 28 days |
| 29 Feb 2000 | 28 Feb 2025 | 25 years, 0 months, 0 days |
| 19 Oct 2000 | 19 Oct 2026 | 26 years, 0 months, 0 days; birthday today |
Different institutions can prescribe different rules for month ends, leap days or rounding. Use the relevant school, assessment or legal instructions for eligibility decisions. This calculator reports a stated calendar convention; it does not determine legal age. Hours are days multiplied by 24, not elapsed hours from a recorded birth time.
Uneven month lengths. Month ends are calculated from the actual calendar, not from a fixed 30-day month.
Leap-day birthdays. In a common year this tool uses 28 February for both the completed-age calculation and the birthday line. On the anniversary itself it displays Today. Legal and institutional rules can differ.
Time zones. The same two entered dates give the same result because the arithmetic uses UTC calendar dates. The default reference date is today in UTC; change it if your local date differs.
Past dates and future dates. Change the reference date to calculate an age at a past event or a future appointment. If birth is after the reference date, the tool asks you to correct the dates.
Enter your date of birth and leave the second field as today. The result is your age in completed years, completed months and remaining days, along with the same age expressed in total months, weeks, days and hours.
Check each tool’s month-end and leap-day convention, whether it rounds months and whether it counts the start date. Two valid conventions can give different year/month/day figures. The total elapsed-days figure is useful for comparison.
The calculation and birthday line both use 28 February in common years. This matches the tool’s month-end clamping rule. On that date the birthday line says Today. Check applicable rules separately when age affects legal rights or eligibility.
Yes — switch the drop-down to “age gap between two people” and enter both dates of birth. The order does not matter; if you enter them the other way round the tool swaps them and says so.
The arithmetic is the same, but assessment work needs the answer in a particular notation and usually at a specific test date. Our chronological age calculator returns years;months, decimal years and total months. Follow the particular assessment manual for rounding and scoring.
No. The calculation runs entirely in your browser. Nothing is transmitted to this site or to anyone else, and nothing is saved when you close the tab.
Updated 19 October 2026: corrected the birthday-today boundary, made leap-day anniversaries consistent, and added worked calendar examples. Published by Talentra Solutions. Report a calculation problem with the two dates and expected convention; please do not send personal records.