Age Calculator
Calculate age in years, months, and days from a date of birth.
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How to use Age Calculator
- Enter the date of birth and any requested comparison date.
- Read the calculated age and check the dates you entered.
Things to check
Age conventions can vary for legal or administrative uses; follow the relevant authority’s rules.
Example task: Calculate age on a particular comparison date
Enter both the birth date and the as-of date. For an illustrative birth date of 1 January 2000, the age on 1 January 2025 is 25 years.
Check the result: Confirm the dates and any legal or administrative convention used by the receiving authority. Today’s age is not necessarily the age needed on a past application date.
Best for
Calculating age through a selected comparison date
What it supports
Date of birth and an as-of date
What you get
Age, total time units, and days to next birthday
Common questions and troubleshooting
Why does an age calculation change when I select another date?
Age is calculated relative to the as-of date, not always today. Use the application deadline or event date when that is what the question requires. Check leap-day birthdays and any legal convention with the receiving authority. This calculator does not decide eligibility for benefits, employment, or legal rights.
More context for this task
Use everyday tools with the right units, dates, and checksProcessing and privacy
Runs in your browser
This tool processes your input on your device instead of uploading it to Toolza. Some tools may save a draft in your browser so you can continue later.
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