stagetimer.io is a free web-based countdown timer. It is designed for communication between speaker and organizer during stage presentations or live events. Multiple internet-connected devices can join the same room ID and display a synchronized countdown. Motivation: A friend of mine has a studio where he mainly records educational content. He uses an old laptop with a little tool written in Flash as a timer. I was thinking: "Surely there is a modern web-based app out there we can use instead." Well, there wasn't. There were some Mac and Windows apps, but nothing like I thought there would be. I thought such a tool must be easy to build. So I built it myself. I wanted to make it possible to put a tablet with wifi somewhere in front of the speaker and remote control it from a laptop or phone by opening a link with a unique key. I believe it can be useful for live events and live stream conferences so that all speakers/organizers can see the same countdown clock by just clicking on a link. Would love to hear your feedback if this is something that fits your use case :)