A customizable, local-first Pomodoro timer for structured sprints, open-ended focus, and everything in between.
Customodoro is a free productivity timer built for people who want more control than a fixed 25-minute countdown. Use the familiar Classic Pomodoro, switch to Reverse Pomodoro when you want to earn breaks from time already focused, and shape the experience with themes, tasks, music, analytics, and distraction-free modes.
No account is required. Your timer, settings, tasks, and productivity history work locally in the browser; an optional account adds cross-device sync and leaderboard participation.
| Mode | How it works | Best for |
|---|---|---|
| Classic | Counts down through customizable work, short-break, and long-break sessions | Study blocks, planned sprints, and repeatable routines |
| Reverse | Counts focused time upward and awards a break based on the work completed | Deep work, creative flow, and tasks with uncertain duration |
Reverse mode includes a standard one-hour workflow and a dynamic mode for longer sessions with configurable break tiers.
- Flexible timers — customize durations, cycle counts, break tiers, auto-start behavior, alerts, and timer ambience.
- Distraction-free focus — Focus Mode, fullscreen controls, and Locked-In Mode with configurable timer, progress, session, and exit controls.
- Tasks that stay useful — add, complete, focus, reorder, and retain tasks while moving between Classic and Reverse modes.
- Progress you can see — contribution-style history, focus points, streaks, completed sessions, productive-day insights, and Classic/Reverse usage.
- A space that feels yours — light and dark modes, built-in visual themes, custom backgrounds, color palettes, and a compact music player.
- Local-first by default — core productivity data and preferences remain in
localStorage; registration is optional. - Optional cloud features — account restoration, cross-device data sync, achievements, and a Supabase-backed global leaderboard.
- Installable web app — PWA metadata and limited static asset caching support an app-like experience on modern browsers.
Customodoro was never planned. It started with a problem.
While preparing for the Pharmacist Licensure Examination, my girlfriend, Clarissa, told me that the usual Pomodoro technique did not work well for her. Stopping after a fixed 25-minute session could interrupt her concentration just when she had found her rhythm. I asked what kind of timer would fit the way she actually studied.
Her answer became Reverse Pomodoro: start like a stopwatch, keep working without an approaching countdown breaking your flow, and earn a longer break from the time you have focused.
The first version followed the break system she imagined:
| Focus time | Break earned |
|---|---|
| 5–20 minutes | 2 minutes |
| 21–30 minutes | 5 minutes |
| 31–45 minutes | 10 minutes |
| 46–55 minutes | 15 minutes |
| 56–60 minutes | 30 minutes |
I built the first MVP while working as an intern. There was no product roadmap, database, account system, or plan to find an audience—I simply wanted to make an app that worked for her while she reviewed for her board exam. As far as I knew, Clarissa would be its only user.
That changed just after midnight on July 9, 2025. Clarissa posted a TikTok to show her appreciation for the timer I had made for her. We expected nothing from it, but the story resonated. Students, reviewees, professionals, and people trying to protect their own focus discovered Customodoro and began suggesting features. A personal project suddenly had a community, and their feedback helped shape the Classic and Reverse timers, customization, analytics, sync, and everything Customodoro has become.
The most meaningful milestone came a few months later: the person who inspired the app, its first user, and the reason it exists passed the November 2025 Pharmacist Licensure Examination. She is now Clarissa Mhae C. Pascual, RPh. What began as a timer for one important goal became a tool that could support many other people through theirs.
Thank you to Clarissa for the idea and for believing it was worth sharing, to every early user who sent feedback or reported a bug, and to Yuya Uzu, creator of Pomofocus, for generously sharing advice and supporting our Product Hunt launch.
Follow the journey: read the full origin story, see the original TikTok post, or follow Customodoro on LinkedIn and X.
To install Customodoro, open the live app in a supported browser and choose Install app or Add to Home Screen.
Coming soon: The Customodoro Browser Extension is on its way to the Chrome Web Store and Microsoft Edge Add-ons, bringing quick access to your focus timer directly from the browser toolbar.
Customodoro has no frontend build step. Clone the repository and serve its static files:
git clone https://github.com/yaaabs/customodoro.git
cd customodoro
npx serve .Then open the local URL printed by serve. Opening the files through a local
HTTP server is recommended because service workers and some browser APIs do not
behave correctly on file:// URLs.
The web app deliberately keeps a small footprint:
- semantic HTML pages;
- feature-oriented CSS;
- vanilla JavaScript loaded directly in the browser;
localStoragefor local-first state;- a separate Express backend for optional account sync;
- Supabase-backed leaderboard reads;
- first-class Privacy Policy and Terms and Conditions pages;
- Node's built-in test runner for timer coverage.
There is no bundler or framework runtime. Scripts communicate through a small
set of window.* APIs, so script order in index.html and reverse.html is
part of the application contract.
npm test # smoke and regression suites
npm run test:smoke # timer lifecycle checks
npm run test:regression # focused regression coverageNode.js 14 or newer is required for the repository scripts.
index.html Classic Pomodoro app
reverse.html Reverse Pomodoro app
pomodoro.html Educational Pomodoro guide
feedback.html Feedback page
privacy.html Privacy Policy
terms.html Terms and Conditions
css/ Shared and feature styles
js/ Timers, settings, sync, stats, audio, and UI
tests/ Browser harness and timer tests
extensions/pomodoro/ Separate browser extension
manifest.json / sw.js PWA metadata and service worker
robots.txt / sitemap.xml Search crawl signals
For deeper implementation details, see
architecture/FRONTEND_ARCHITECTURE.md.
Note
Customodoro is installable and caches its core timer and legal pages, but it should not be described as fully offline: account sync, leaderboard data, the external feedback form, and some restoration paths still require network access.
Bug reports, focused fixes, and thoughtful feature improvements are welcome. Please preserve the static architecture, local-first data model, timer single-completion guards, and behavior across both timer pages. Run the narrowest relevant test suite before opening a pull request.
Customodoro is available under the MIT License.
Built by Brian Yabut (YabuTech) for anyone trying to make focus fit the way they actually work.