Age Calculator
See your age in calendar years, months, and days, or check total days and the date of your next birthday.
- 2026 figures, checked October 26, 2026
- Private: runs in your browser
- How we check our work
Result
…
Verify before you act: review these results with a qualified professional before making any decision based on them.
Suggestions for your numbers
Updated as you type, from your inputs only. General information, not personal advice; confirm any change with a qualified professional.
See it over time
Hover over or tap the chart to see the numbers for any point.
What is an age calculator?
An age calculator works out how much time has passed between your date of birth and a date you choose. It answers “how old am I?” as a calendar age in full years, months, and days.
A chronological age calculator uses the calendar, rather than estimating from a number of days. It counts full years, then months, then days. A birthday calculator can also show your next birthday and the day of the week you were born.
Why your exact age matters
Your age can help you organize personal and financial plans. You might use it to review a retirement timeline, prepare for an insurance conversation, or check a date tied to a benefit or account. The calculator gives you a date-based starting point; it does not determine whether you qualify for a program or make a financial decision for you.
An exact age can also help when you are filling out a form or checking a family timeline. If a rule depends on age, read the rule itself and confirm how it defines age. For retirement, insurance, tax, or other regulated decisions, confirm your situation with a qualified professional.
How to use this age calculator
- Enter your date of birth. Check the month, day, and year carefully before calculating.
- Enter the date you want to measure your age as of. This can be a date other than today if you are checking a past or future date.
- Review the result in years, months, and days. Then check total months, weeks, and days if you need a single-unit count.
- Use the next-birthday result to see the upcoming birthday date and how many days remain from the selected as-of date.
Age calculator example
Worked example
With a date of birth of 1990-06-15 and an age-as-of date of 2026-10-26, the result is 36 years, 4 months, 11 days old. That is 36y 4m 11d, 436 total months, 1,897 total weeks, and 13,282 total days. The person was born on a Friday. The next birthday is Tuesday, June 15, 2027, in 232 days. The result follows the stated method: count full years, then months, then days between the dates.
How to read your age calculator results
Years, months, and days gives your calendar age at the date you entered. It is the clearest result when someone asks for your exact age. Total months expresses the same elapsed time in months; it is not a separate measure of age.
Total days shows the elapsed days between the two dates. Total weeks shows the completed weeks in that span. Your birth weekday identifies the day of the week for your date of birth. Next birthday gives the next birthday after the as-of date and the time remaining to it.
How to get a more useful age result
- 01
Check the birth date against a reliable record
A mistyped month or day changes every result. Verify the date before using the result for a form, planning conversation, or family record.
- 02
Choose the right as-of date
Use the date that matches the question you are answering. For a past event, enter that event's date rather than assuming the calculator is measuring age today.
- 03
Connect the result to a decision
If you are reviewing when to retire, borrow, or change coverage, pair your age with the relevant account terms, costs, and dates. Ask a qualified professional to confirm rules that affect taxes, retirement, or insurance.
Common age calculator mistakes
Using the wrong date format
Read the input labels and enter the date in the format the calculator requests. Recheck the year as well as the month and day.
Treating total months as full months lived in every context
Total months is a convenient way to express elapsed time. It does not replace the years-months-days result when a form or rule asks for calendar age.
Assuming an age result decides eligibility
A calculator reports elapsed time between dates. It does not interpret a benefit, contract, or program's terms. Check the applicable rules before relying on the result.
The age formula
Counts full years, then months, then days between the two dates.
Key terms
- Chronological age
- The time between a person's date of birth and a selected date, counted using calendar years, months, and days.
- Total months
- Elapsed time expressed in months rather than as years, months, and days.
- Total days
- The number of elapsed days between the date of birth and the selected as-of date.
- Next birthday
- The next occurrence of your birthday after the selected as-of date.
Age questions
What does “age as of” mean?
It is the date through which the calculator measures your age. Changing this date changes the result, even when your date of birth stays the same.
Why are years, months, and days more useful than total days?
Calendar age is easier to understand for everyday questions and many forms. Total days is useful when you specifically need the elapsed day count.
Can I calculate my age on a past date?
Yes. Enter the past date in the age-as-of field to see how old you were then.
Does the next-birthday countdown use the as-of date?
Yes. It shows the next birthday after the date you entered and the days remaining from that date.
Before you act on this result. Cordwell calculators and guides are educational estimates, not legal, tax, investment, lending or other professional advice. They rely on the numbers you enter and on simplified rules, and they can't see your full situation. Before you file, sign, borrow, invest, hire, change your withholding or form a business based on anything here, meet with a qualified professional who can review your specific facts and confirm the numbers. Rules change, and official agency guidance always controls.