Age Calculator

Worked example

Example: date of birth 15 March 1990 calculated on 1 January 2026 gives 35 years, 9 months, and 17 days.

When to use this

• Filling forms that ask for exact age in years, months, and days on a specific date.
• Checking school enrollment cutoff eligibility for a child on the district's reference date.
• Verifying retirement or benefits age against a policy's required birthday.
• Planning milestone birthdays or counting days until the next birthday.

Common examples

• Born March 15, 1990 → age on July 7, 2026 is 36 years, 3 months, 23 days.
• School cutoff Sept 1 → compare two children's ages on that date for kindergarten eligibility.
• Retirement planning → age in years and months on a target retirement date.
• Birthday countdown → days until next birthday from today's date.
• Form entry → exact age in years, months, and days for insurance or travel paperwork.

Common mistakes

• Swapping day and month when entering dates in DD/MM versus MM/DD format.
• Using today's date when the form requires age as of a past or future reference date.
• Confusing total days lived with years multiplied by 365.
• Expecting fractional years to match years-months-days breakdown without calendar math.

How it works

Calculates the exact age from a date of birth to a chosen date by counting complete years, then months, then days. Future dates of birth are rejected.

Limitations

Counts calendar years, months, and days between dates. Does not account for time zones or leap-second adjustments.

Privacy and file handling

Your data stays on your device and is not uploaded.