Age Calculator
Calculate age
Methodology & standardsRuns on your device
Inputs
Results update liveInterpretation
How Age Calculation works
The Age Calculator measures the calendar difference between a past birth date and today. It handles month-end and leap-day anniversaries by using the final valid day of the anniversary month.
Example
Key features
A realistic scenario showing how the calculation guides a practical decision.
Formula
Age = today minus birth date, using calendar-month anniversaries
- Calculates age in calendar years, months, and days
- Accounts for leap years and varying month lengths
- Shows an approximate decimal-year view
- Rejects future dates
Watch out
Common mistakes
- For legal, benefits, or eligibility decisions, verify the governing organisation's exact age-date convention.