Age Calculator

How it works

Enter a birth date and, optionally, a target date. The tool compares calendar years, months, and days, borrowing across months or years as needed, then also reports the total number of days between the two dates.

Benefits

• Uses real calendar arithmetic, not a rough day-count estimate
• Supports any target date, not just today
• Shows both years/months/days and a total day count
• Calculates instantly with no upload of personal dates

Use cases

• Find someone's exact current age
• Calculate age as of a specific eligibility or event date
• Count the exact days until or since a milestone
• Check age requirements for enrollment or legal thresholds

Best practices

• Leave the target date blank to use today automatically
• Use a specific target date for eligibility or legal deadlines
• Double-check date formats match YYYY-MM-DD
• Use total days when you need an exact day count, not just years

Common mistakes

• Assuming age in years equals total days divided by 365
• Entering a target date earlier than the birth date
• Forgetting leap years can shift day counts near February 29
• Mixing up day and month order when typing dates manually

Privacy

Birth dates and target dates are processed entirely in your browser. Age Calculator does not upload or store this information on any server.