DEV3 Free Countdown and Pomodoro Timer — Source Code (React + Tailwind)

Source code of the DEV3 Countdown and Pomodoro Timer, an event countdown with a shareable URL and a Pomodoro timer with configurable cycles, WebAudio chime and browser notifications.

Free download: sign in to any DEV3 account and click Download ZIP. Try it live: https://dev3.tech/tools/countdown-pomodoro-timer shows the finished tool running.

What is in the download

• A standalone Vite + React + TypeScript + Tailwind CSS project: src/tool holds the tool, shared pieces sit beside it
• package.json with exact versions plus a lockfile, so npm ci works
• README.md (run, build, embed in Next.js or plain React) and an MIT LICENSE

What the code does

• Share link stores the UTC instant so any time zone sees the right countdown
• Clock-based timers that stay accurate in throttled tabs
• Work, short break and long break sequence builder
• Web Audio beep and Notification API alerts, no audio files

Tech stack

React 19, TypeScript, Vite, Tailwind CSS 4.

Install and customise

The How to install and How to use tabs list the steps. In short: unzip, npm ci, npm run dev, then copy the tool folder into your own app if you want to embed it.

Good to know

• A browser-only tool: there is no backend or database in the code.
• Timers need the tab open; there is no background service worker.