Navigate to [https://calendar.google.com/calendar/u/0/r/](https://calendar.google.com/calendar/u/0/r/)

Click the checkbox next to "Speedy meetings"

This will automatically make 30 minute meetings 25 minutes and longer meetings 10 minutes meetings shorter than they would otherwise be (e.g., 60 -> 50 minutes).

As a courtesy, it's also good to allow your guests to modify the event. Click the "default guest permissions dropdown."

Google Calendar

These two settings will have you in better meetings in no time! Learn about "speedy meetings" and "guest permissions."

How to Be More Productive with Google Calendar