Age Calculator
Find an exact age in years, months and days, plus total days lived and days until the next birthday.
Enter a date of birth and the date you want to measure against. The calculator returns a calendar accurate age that accounts for different month lengths and leap years, in US date style.
Enter a date of birth to see an exact age.
How to use this tool
Pick the date of birth, then adjust the second date if you want the age on a future or past day. Press Calculate age.
Example use case
A parent checks whether a child will be 5 years old before the September kindergarten cutoff date.
Limitations and accuracy notes
Calculations use calendar dates only and ignore time of day and time zones. For legal or medical purposes, confirm the result with the relevant official source.
Frequently asked questions
Does it handle leap years?
Yes, February 29 is counted correctly.
Can I calculate a future age?
Yes, set the second date to any future day.
What date format is used?
Dates follow the US style, month then day then year, in the displayed result.
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