Age calculator
Find an exact age in years, months and days on any date, with totals in months, weeks and days and a countdown to the next birthday.
- 100% free
- Runs in your browser
- No uploads
Age
Enter a date of birth to see the age.
- Runs on your deviceEvery tool works directly in your browser. No files are uploaded.
- Your privacy mattersYour files never leave your device, so there's nothing for us to store.
- No limitsUse any tool as much as you need. No daily caps, no waiting.
- Completely freeNo signup and no trial to cancel. Ads keep the tools free.
How to use the age calculator
- Enter the date of birth. Use the date picker or type the date.
- Pick the date to measure to. It starts as today. Change it to see an age on any other day, such as a deadline or an anniversary.
- Read the result. You get the age in years, months and days, the same span in total months, weeks and days, and the date and weekday of the next birthday.
How age is counted
The calculator counts whole months from the date of birth, then splits them into years and months. The days are what's left between the last monthly mark and the date you measure to. This is how people normally state age, and it means the year and month counts only go up on the day they're reached.
Short months. When a month has no matching day, the mark falls on the month's last day. Someone born on January 31 is one month old on February 28 (or 29 in a leap year), and two months old on March 31.
Leap day birthdays. Someone born on February 29 turns a year older on February 28 in years without a leap day. The calculator tells you when it uses this rule.
Totals. Total days is simply the number of days between the two dates, counting every leap day. Weeks are those days divided by 7, with the remainder shown in days.
Worked examples
| Born | Age on | Age |
|---|---|---|
| May 15, 1990 | October 8, 2026 | 36 years, 4 months, 23 days (13,295 days) |
| January 31, 2023 | March 1, 2023 | 1 month, 1 day |
| February 29, 2000 | February 28, 2001 | 1 year, 0 months, 0 days |
| February 29, 2000 | February 29, 2024 | 24 years (8,766 days) |
Why age calculators sometimes disagree
Most differences come from the days part near the end of a month. Some tools count the leftover days using the length of a different month, so an age that ends just after a short month like February can come out a day or two apart. Total days never changes, so use it when you need a figure everyone will agree on.
For an age requirement, such as turning 18 or 65, the year count is what matters, and it's the same in every method except for February 29 birthdays.
Frequently asked questions
How do I calculate my exact age?
Count the whole years since your last birthday, then the whole months since that birthday's month-day, then the days left over. Born May 15, 1990, on October 8, 2026 you are 36 years (May 15, 2026), 4 months (September 15) and 23 days old.
When does someone born on February 29 have a birthday?
In leap years, on February 29. In other years this calculator uses February 28, the last day of February, so the age goes up before March starts. Some laws and organisations count March 1 instead, so check the rule that applies to you if it matters legally.
Why is a month from January 31 on February 28?
February has no 31st, so the one-month mark falls on its last day. Months are always counted from the birth date itself, so the two-month mark is back on March 31. This is the same rule most date software and contracts use.
Can I find an age on a past or future date?
Yes. The “Age on” date starts as today, but you can change it to any date after the date of birth, for example to check how old someone will be on their wedding day or was on a past school cutoff date.
Does the time of day or time zone matter?
No. The calculator compares calendar dates only, so it doesn't matter what time you were born or where. Today's date comes from your device's clock and time zone.