Age & DatesDATE & AGE TOOL
Life Milestones Calculator
See the calendar dates when you reach important ages from 18 through 100.
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 will I reach an age milestone?
Enter your birth date to see the dates and weekdays of your 18th, 21st, 30th, 40th, 50th, 60th, 70th, 80th, 90th and 100th birthdays. These are calendar milestones, not legal eligibility advice.
Worked example
Someone born on 1 January 2000 reaches their 30th birthday on 1 January 2030.