Date & time Age

Age difference calculator

From

Counting

Age difference —

The same gap in other units

Days —

Weeks —

Whole weeks —

Months —

Years —

Hours —

Minutes —

Note Enter both dates

The gap never changes

The age difference between two people is the gap between their birth dates, and it never changes. Someone born in 1990 and someone born in 1994 are always four years apart, whatever ages they happen to be.

How to find an age difference

1 Enter both birth dates.

2 Read the years, months and days between them.

3 The totals in each unit are underneath.

4 Order does not matter — the gap is the same.

The constancy is what people get wrong. A four-year gap feels enormous between a six-year-old and a two-year-old and negligible between a fifty-year-old and a forty-six-year-old, but the gap itself has not moved. What changes is the ratio: four years is twice the whole life of the younger child in the first case and under a tenth in the second, which is why the same gap reads so differently at different stages.

Questions

Does an age gap change over time? −

No. The gap between two birth dates is fixed; what changes is how large it feels relative to their ages.

How do I calculate an age difference? +

Does it matter which date I enter first? +

Why does the same gap feel different? +

Can I use it for events rather than people? +

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