Lunar Birthday Calendar Generator (https://lunar-birthday-calendar-web.firebaseapp.com)
Google Calendar/Outlook does not allow you to create recurring events based on lunar calendar (e.g. Grandma/Grandpa's birthdays.)
This little tool generates an ICS calendar file for you. You can then import the generated ICS file into Google Calendar/Outlook so it's easy to remember when to call/visit them on their birthdays 🎂
[This is a webified-version of bluishoul's nice utility]
[Credits: lunar-birthday-calendar https://www.npmjs.com/package/lunar-birthday-calendar]