Age Calculator
Exact age in years, months, and days from a birth date.
Result
Fill in the inputs to see your result.
Inputs
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Quick answer
Age Calculator: in one paragraph
An age calculator finds the exact gap between two dates and expresses it in years, months, and days — handy when 'years old' alone isn't precise enough.
What this calculator does
Pick a birth date and a reference date (today by default). The calculator subtracts the two and breaks the result into full years, remaining months, and remaining days, accounting for leap years and varying month lengths.
Why people use it
- Fill in forms that need exact age in years and months.
- Work out age on a specific past or future date — useful for eligibility cutoffs.
- Compare two ages, or measure how long since a milestone.
- Verify someone's age for school, sport, or legal cutoff dates.
A worked age calculation
A concrete walkthrough you can follow line by line.
Born 14 March 1995, today is 11 May 2026.
1. Full years
From 14 March 1995 to 14 March 2026 = 31 years
2. Remaining months
From 14 March 2026 to 14 April 2026 = 1 full month
3. Remaining days
From 14 April to 11 May = 27 days
Result
31 years, 1 month, 27 days old.
When to use this calculator
- Verifying eligibility (school year, voting, retirement, sports brackets).
- Calculating someone's age as of a future event date.
- Tracking infant or pet age in months and weeks rather than years.
Common mistakes
- Off-by-one errors around the birthday — your year only ticks up the day you turn the next age.
- Forgetting that February has 28 or 29 days when subtracting calendar months.
- Using the wrong reference date (today vs the event date) for eligibility cutoffs.
Quick questions
How does it handle leap years?+
By using calendar arithmetic rather than a fixed 365-day year. The number of days between two dates is computed directly, so leap days are included where they actually fall.
Can I calculate age on a future date?+
Yes — set the reference date to any future day. The result tells you exactly how old someone will be on that date.
Learn more
Deeper reads from the Calcxo learn library.
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Revision history2 changes · last on Jan 12, 2026⌄
- AccuracyFixed an off-by-one when the birth date falls on a leap day.
- ReleasedInitial release.