Age in Years, Months, and Days

Worked example

Example: born January 10, 2022, as of September 1, 2025 → 3 years, 7 months, 22 days.

When to use this

• School enrollment age verification.
• Pediatric dosing or growth chart context.
• Immigration or visa age documentation drafts.

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

• Rounding fractional years instead of using calendar months.
• Forgetting months are counted from the birth day-of-month.
• Using UTC dates when local calendar date is required.

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.