Age Calculator
Enter a date of birth and the calculator shows how old someone is right now: exact years, months and days, and also the same age expressed as total months, weeks and days. Change the age-at date to find the age on any other day, past or future.
Results
Your age
36 years, 4 months, 6 days
- Total months
- 436
- Total weeks
- 1,896
- Total days
- 13,278
- Next birthday
- Saturday, 15 May 2027
- Days until next birthday
- 236 days
- Born on a
- Tuesday
Born on 15 May 1990, the age on 21 September 2026 is 36 years, 4 months, 6 days.
Show the calculation steps
- Count complete years and months from 15 May 1990 to 21 September 2026: 36 years and 4 months (the last one completed on 15 September 2026).
- Count the remaining days after that date: 6 days.
- Total time lived = 13,278 days = 1,896 weeks and 6 days.
- The next birthday is on Saturday, 15 May 2027.
- Dates are counted as calendar dates, so time zones do not affect the result.
How age is calculated
The calculator counts complete calendar months from the date of birth to the chosen date, then splits them into years and months. The days are what remain after the last completed month.
If a date does not exist in a shorter month, for example the 31st, it is treated as the last day of that month. Leap years follow the standard Gregorian calendar rules.
Born on 29 February
People born on a leap day have a real birthday only every four years. In other years this calculator counts the birthday on 28 February. Some legal systems use 1 March instead, so check the rule that applies to you when it matters.
Useful ways to use it
- Check the exact age needed for a form, exam or eligibility rule.
- Find someone's age on a past or future date using the age-at date.
- See how many days until the next birthday.
Formula
Age = complete years + complete months + remaining days between the two dates
Total days = date of the age calculation − date of birth
Where:
- Years, months
- = Complete calendar years and months since the date of birth
- Days
- = Days left over after the last completed month
Example calculation
Born on 15 May 1990, age on 19 September 2026
Inputs
- Date of Birth
- 15 May 1990
- Age at Date
- 19 September 2026
Result
- Your age
- 36 years, 4 months, 4 days
- Total months
- 436
- Total weeks
- 1,896
- Total days
- 13,276
- Next birthday
- Saturday, 15 May 2027
- Days until next birthday
- 238 days
- Born on a
- Tuesday
Step-by-step
- Count complete years and months from 15 May 1990 to 19 September 2026: 36 years and 4 months (the last one completed on 15 September 2026).
- Count the remaining days after that date: 4 days.
- Total time lived = 13,276 days = 1,896 weeks and 4 days.
- The next birthday is on Saturday, 15 May 2027.
Important notes
- Results are based on calendar dates, so time zones and daylight-saving changes cannot move the answer by a day.
- When the age-at date is blank, today's date from your device is used.
Disclaimer: This calculator provides estimates for informational purposes only. Check important results independently before relying on them.
Frequently asked questions
How do I calculate my exact age?
Count the complete years from your date of birth to today, then the complete months after that, then the remaining days. The calculator does this for you and also gives the totals in months, weeks and days.
Can I find the age on a specific date?
Yes. Fill in the Age at Date field with the date you are interested in, for example a future deadline or a past event. Leave it blank to use today.
How are leap years handled?
The calculator uses the Gregorian calendar, so a year is a leap year when it is divisible by 4, except century years not divisible by 400. Total days lived include every leap day between the two dates.
Why might my age differ from another calculator?
Some tools count months as 30 days or ignore the varying length of months. This calculator counts real calendar months, which is the standard way to state an age.
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