Half Birthday Calculator
Calculate the "half-anniversary" of a world-changing event.
The Next Half Birthday/Anniversary is:
A half-birthday occurs exactly six months after your actual birthday. It is a popular milestone for tracking Infant Development and for children with birthdays during school breaks. While waiting for your real birthday, why not check your Age in Seconds?
This tool calculates the precise 6-month midpoint. Because month lengths vary, this ensures you find the mathematically correct day. You can also find your 10,000-Day Milestone or see when your Dog hits their next human-equivalent year.
Half Birthday Questions
When is 6 months after my birthday?
Enter your birth date above! For years/months/days, see the Age Calculator.
What if I was born on Aug 31st?
Your half-birthday is Feb 28th (or 29th). See our Index for leap year info.
How many days in a half-year?
About 182. See your Live Seconds Count for precision.
Why celebrate a half-birthday?
It's an "unbirthday"! See more fun milestones on the Milestones Page.
Can I calculate this for my cat?
Yes, use the Cat Age Tool to see their half-year stage.
Does this work for past years?
Yes, or use How Old Was I? to see your age on past half-birthdays.