Age & DatesDATE & AGE TOOL
Next Birthday Calculator
Find the date of your next birthday and the age you will turn.
How this calculator works
This tool uses calendar dates directly. Date differences are calculated from UTC-normalized calendar dates to avoid daylight-saving-time changes affecting the result. Calendar age counts complete months from the starting date, then remaining days. When a month is shorter, the date is clamped to its last day. For this tool, a 29 February birthday is observed on 28 February in a non-leap year. These are calculation conventions, not legal eligibility rules.
Why use this tool?
It is designed for quick, transparent calculations without requiring an account. Your date inputs are processed in your browser by the current version of the site.
Frequently asked questions
Does this calculator account for leap years?
Yes. Calendar calculations use the actual dates in the Gregorian calendar, including leap years.
Do you store my date of birth?
The calculator processes dates locally in your browser. We do not send the entered dates as analytics events. See our privacy information for site analytics details.
Keep exploring
When is my next birthday?
The next birthday is the first anniversary on or after the selected calculation date. If the birthday has already passed in that year, the tool uses the next year. A 29 February birthday is observed on 28 February in a non-leap year.
Worked example
For someone born on 18 May 1990, calculating as of 19 May 2026 gives a next birthday of 18 May 2027.