Age Calculator from Date of Birth

Worked example

Example: born March 15, 1990, calculated on July 7, 2026 → 36 years, 3 months, and 23 days (plus total days lived).

When to use this

• Filling forms that ask for age on a specific date.
• Verifying eligibility for programs with age cutoffs.
• Planning milestone birthdays or anniversaries.

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 in DD/MM versus MM/DD locales.
• Using timezone midnight when the birth time matters for same-day edge cases.
• Confusing total days with years × 365.

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.