How to Calculate Age from Date of Birth

Whether you are filling a government form, checking exam eligibility or celebrating a birthday milestone, you often need your exact age — not just years, but months and days too.

Calendar age vs total days

Calendar age counts full years, then remaining months, then remaining days between two dates. This matches how most official forms expect age to be reported.

Total days lived is simply the number of days between birth date and reference date — useful for anniversaries and precise durations.

Step-by-step manual method

1. Start with the later date (usually today).
2. Subtract birth year from reference year.
3. If the reference month is before the birth month, subtract one year.
4. Adjust months and days if the day-of-month has not yet occurred.

Leap years matter: February 29 birthdays and leap years affect day counts.

Example

Born 15 June 1995, reference date 20 June 2026:

• Age: 31 years, 0 months, 5 days

Common use cases in India

• Government and exam forms — exact age as on a cutoff date.
• Insurance applications — age bands affect premiums.
• Scholarships and schemes — eligibility windows.
• School admissions — age cutoffs for entry classes.

Avoid these mistakes

• Dividing total days by 365 for “years” — inaccurate across leap years.
• Using only year difference — ignores month and day boundaries.
• Forgetting timezone when using automated systems (rare for DOB forms).

Use the free age calculator

MerQPrime’s age calculator computes years, months, days and total days instantly. You can also set a custom reference date to see age on a past or future date.

No data is uploaded — everything runs in your browser.