Age calculator
Your exact age on any date, from your DOB.
Open toolDays in month
Count days in any month and year.
Your input stays in this browser. No account needed.
THE QUICK GUIDE
How to use days in month
Enter the labelled values, then process it. Copy or download the result.
How it works
Uses Gregorian month lengths and the leap-year rule.
A useful example
Year (1–9999): 2028; Month (1–12): 2 → 29 days
Good to know
Use consistent units and currency. These are general calculations; verify important results.