Try it live at https://reminders-tool.web.app/
This repo is the source code, if you'd like to self-host with your own Firebase backend. See the README for setup instructions.
You are also welcome to use Reminders Web exclusively by using the above link. With this project in particular, I am also footing the server bill for those who don't plan to self-host. If that's you, consider donating to help offset the server usage costs – but by no means a requirement :) Either way, thanks for checking it out!