How to use this calculator
A calendar-accurate age and date difference tool, using real month lengths and leap years.
Exact calendar dates
Enter a valid starting date and an as-of date on or after the start. The result includes calendar years, months and days.
Next birthday
For February 29 births, the next birthday is observed on March 1 in non-leap years for this calculator.
Privacy
The dates stay in your browser for the calculation. Shared scenario links can contain dates if you explicitly choose to share.
Useful resources, not just numbers.
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