MyAgeCalc

Chronological age calculator

For psychologists, teachers and SLPs scoring a test — with every borrowing step shown, so you can check it against your protocol.

Test date
Date of birth

When borrowing days

Step by step

YearMonthDay
Test date202634
− Birth date20171019
= Age

Write the test date on top and the birth date underneath, as year · month · day.

Showing an example. Enter both dates above to see your own.

Reading the result

Test manuals usually record chronological age as years;months. A child who is 8 years, 4 months and 16 days old is written 8;4. Check your manual on whether to round up when the days are 15 or more — some tests do, most don't.

Use the same convention as your scoring software: most publishers borrow a flat 30 days, which is this calculator's default.

Questions

What is chronological age?

Chronological age is the exact time a person has been alive, written in years, months and days. It is the starting point for scoring standardised tests, where results are compared with others of the same age.

How do you write chronological age on a test protocol?

Most test manuals use the format years;months — for example 8;4 means 8 years and 4 months. Some also record the days, and some round up when the days are 15 or more; always follow your test manual.

Do you borrow 30 days or the real length of the month?

Most test publishers tell examiners to borrow 30 days whatever the month. A few scoring programs use the real number of days in the previous month, which can change the day count by one or two.

What is the difference between chronological age and biological age?

Chronological age is simply time since birth. Biological age is an estimate of how old your body seems based on health markers, and can be higher or lower than your chronological age.

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