Age Calculator

Work out an exact age in years, months and days, plus the clinical years;months format, and see the dates you reach every age that changes something — including your own Social Security full retirement age and RMD age, derived from your birth year.

Every convention this page applies is named in the result rather than assumed. Your numbers stay in this browser.

Enter a date of birth. Everything else is optional: a time of birth sharpens the hour totals, and a second date of birth compares two ages.

Date of birth ?

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Measured to ?

Leave blank for today. Set a future date to see an age on a birthday, a school cut-off, or a benefits date.

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How age is counted ? ?

Only applies to a 29 February date of birth. The convention used is named in the result.

Optional comparisonsoptional
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Results

How to read this: the verdict describes how much room your numbers leave, not a decision or an offer. Change any input to see how much the result moves.

Assumptions and formula

This calculator uses the standard fixed-rate repayment schedule, keeps full precision internally, and rounds currency only for display and export.

Every date is computed in UTC, so a daylight-saving change cannot shorten or lengthen a counted day. Months are whole calendar months, found by advancing from the date of birth and clamping to the target month rather than borrowing an averaged 30 days.

Worked example

A fixed-rate monthly repayment scenario produces a payment schedule that reduces principal until the balance reaches zero.

Frequently asked questions

When do I reach Social Security full retirement age?

It depends on the year you were born and it is not 67 for everyone: 66 for those born 1943-1954, stepping up two months per birth year to 67 for 1960 onward. This page derives your own figure from your birth year and gives the date, alongside the RMD age, which has three cohorts under SECURE 2.0.

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