# Age Calculator

> Find exact age, total days, and the next birthday from two dates.

Page: https://askcalculators.com/calculator/age-calculator/
Definition: https://askcalculators.com/calculator/age-calculator/definition.json
JSON Schema: https://askcalculators.com/calculator/age-calculator/schema.json
Version: 1.0.0
Maintained by: AskCalculators (software project; not a credentialed reviewer)
Qualified review: pending. Automated checks do not establish professional approval.
Page status: Live
Review status: Pending

## Use
Open the calculator page and enter values. Query-string parameters can restore and bookmark a calculation.
Example: https://askcalculators.com/calculator/age-calculator/?birthDate=1990-01-01

## Inputs
- birthDate: Date of birth; type=date; required; default=1990-01-01
- targetDate: Age on date; type=date; optional; default=today

## Outputs
- exactAge: Exact age; format=text; primary
- totalDays: Total days; format=integer
- nextBirthday: Next birthday; format=date
- daysToBirthday: Days until next birthday; format=integer

## Formula
Exact calendar difference = target date − birth date

Month length and leap years are handled as calendar dates, not average day counts.

## Rules
- Empty optional inputs are undefined, not zero.
- Hidden conditional inputs are ignored.
- Do not invent missing required inputs.