Does the order of the dates matter?

No. The gap between two people is the same size whichever way round you enter them, and the calculator reports which date came first separately. That is different from the age calculator, where the direction genuinely matters.

Why not just subtract the years?

Because it is wrong by up to a year. Two people born in 1990 and 1994 might be three years and one day apart, or nearly five years. It depends entirely on the months and days. Subtracting birth years answers a different, vaguer question.

How are months counted?

Whole calendar-month anniversaries come first, followed by remaining calendar days. A 31 January anniversary clamps to the last day of February. A 29 February anniversary uses 1 March in common years, matching Age Calculator. Whole weeks are the total calendar days divided by seven, rounded down; the summary shows the remainder.

What counts as a large age gap?

That is a social question rather than a mathematical one, and the answer varies by culture, context and the ages involved. A four-year gap means something very different at 16 than at 46. The calculator gives you the number; what it means is not something arithmetic can settle.

Can I use this for anything other than people?

Yes, for a literal calendar distance between two supplied dates. If your interval includes times of day or you need elapsed hours and minutes, use Duration Calculator; it states its own endpoint and leap-day conventions.

Are the dates stored anywhere?

Saved dates are read only when the page opens. Valid deliberate calculations are saved in this browser; incomplete or invalid edits keep previous saved dates. Unusable records stay until you choose Forget saved dates. Nothing is uploaded.

Is this a dating or socially acceptable age-gap rule calculator?

No. A difference between birth dates does not establish whether dating or marriage is suitable or socially acceptable. This page does not apply the half-your-age-plus-seven rule, assess a relationship, or predict pregnancy or conception.

Which dates can I enter?

Real Gregorian dates from 0001-01-01 through 9999-12-31. The fields are literal calendar dates, including a date skipped by a local clock change. Total days are calendar distance, not elapsed 24-hour periods. Historical local calendar reforms are not modeled.

Age Gap Calculator

Compare two birth dates to find their calendar gap in years, months and days, total calendar days and whole weeks, and which person is older. Use it for siblings or any two supplied dates. The calculation measures a difference; it does not judge a relationship.

Age gapReadyPick two dates of birth

First date of birth: No date selected

Second date of birth: No date selected

Common questions

Does the order of the dates matter?: No. The gap between two people is the same size whichever way round you enter them, and the calculator reports which date came first separately. That is different from the age calculator, where the direction genuinely matters.
Why not just subtract the years?: Because it is wrong by up to a year. Two people born in 1990 and 1994 might be three years and one day apart, or nearly five years. It depends entirely on the months and days. Subtracting birth years answers a different, vaguer question.
How are months counted?: Whole calendar-month anniversaries come first, followed by remaining calendar days. A 31 January anniversary clamps to the last day of February. A 29 February anniversary uses 1 March in common years, matching Age Calculator. Whole weeks are the total calendar days divided by seven, rounded down; the summary shows the remainder.
What counts as a large age gap?: That is a social question rather than a mathematical one, and the answer varies by culture, context and the ages involved. A four-year gap means something very different at 16 than at 46. The calculator gives you the number; what it means is not something arithmetic can settle.
Can I use this for anything other than people?: Yes, for a literal calendar distance between two supplied dates. If your interval includes times of day or you need elapsed hours and minutes, use Duration Calculator; it states its own endpoint and leap-day conventions.
Are the dates stored anywhere?: Saved dates are read only when the page opens. Valid deliberate calculations are saved in this browser; incomplete or invalid edits keep previous saved dates. Unusable records stay until you choose Forget saved dates. Nothing is uploaded.
Is this a dating or socially acceptable age-gap rule calculator?: No. A difference between birth dates does not establish whether dating or marriage is suitable or socially acceptable. This page does not apply the half-your-age-plus-seven rule, assess a relationship, or predict pregnancy or conception.
Which dates can I enter?: Real Gregorian dates from 0001-01-01 through 9999-12-31. The fields are literal calendar dates, including a date skipped by a local clock change. Total days are calendar distance, not elapsed 24-hour periods. Historical local calendar reforms are not modeled.

Exact literal Gregorian calendar arithmetic from 0001 through 9999. Independent of daylight saving and skipped local dates. Short months clamp; 29 February anniversaries use 1 March in common years. No elapsed-time or relationship assessment.