How to interpret this estimate

Estimate age as of the current date. Uses the current date in the user's browser and a Gregorian calendar date of birth.

When this result is useful

Use this calculator to compare how Birth year, Birth month, and Birth day change Completed age, Approximate days lived, and As of date, and to review alternative values before using the estimate for planning.

Common limitations

Completed years decrease by one when the birthday has not yet occurred in the current year. Time zone differences can shift the displayed reference date by one day near midnight. Review the units and assumptions before interpreting the result.

This calculator uses the selected inputs and the fixed formula behind the tool to produce an estimate. Review the units, assumptions, and result labels before using the output for planning.

Health results are screening or planning estimates only. They do not diagnose health status or replace advice from doctors, dietitians, or qualified healthcare professionals.

Read the medical disclaimer for more context.