Pomodoro Timer

Focus timer with customizable work and break intervals, task tracking with estimated pomodoros, desktop notifications, and session analytics. Runs entirely in your browser.

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How to Use

The Pomodoro Timer helps you maintain deep focus by structuring your work into timed intervals with regular breaks. It implements the Pomodoro Technique automatically, so you can concentrate on your tasks instead of watching the clock.

Getting Started

Add your tasks: Enter what you want to work on in the task input field and set an estimated number of pomodoros for each task. Press Enter or click the plus button to add.
Select an active task: Click a task to highlight it as your current focus. Completed pomodoro counts will automatically increment for the active task.
Start the timer: Click Start or press Space to begin a 25-minute focus session. The circular progress ring fills as time passes.
Take breaks: When a work session ends, the timer automatically transitions to a 5-minute short break. After four work sessions, you get a 15-minute long break.
Track progress: The session stats bar shows your completed sessions today, current cycle position, task completion rate, and estimated versus actual pomodoro counts.

Customization

Click the gear icon to open Settings. You can adjust work duration (1-120 minutes), short break (1-30 minutes), and long break (1-60 minutes). Toggle auto-start to control whether the next session begins automatically. Enable desktop notifications via the bell icon to receive alerts when sessions end, even when the tab is in the background.

About This Tool

The Pomodoro Technique

The Pomodoro Technique was developed by Francesco Cirillo in the late 1980s while he was a university student in Rome. Named after the tomato-shaped kitchen timer he used, the method divides work into 25-minute focused intervals called "pomodoros," each followed by a short break. After completing four pomodoros, a longer break of 15-30 minutes provides deeper recovery. As of 2025, the technique has been adopted by millions of knowledge workers, developers, and students worldwide, with research from the Journal of Applied Psychology (2022) confirming that structured work-break cycles improve sustained attention by 15-25% compared to unstructured work sessions.

Why 25 Minutes Works

The 25-minute work interval is grounded in cognitive science. Human focused attention naturally degrades after 20-30 minutes of continuous effort. A 2021 meta-analysis of 40 studies found that attention performance peaks around 20 minutes and begins declining around 25-30 minutes. The Pomodoro interval captures this optimal window: long enough to achieve meaningful progress on complex tasks, short enough to maintain peak concentration. The mandatory breaks prevent the cognitive fatigue that accumulates during extended work sessions, which studies link to increased error rates and reduced creative problem-solving.

Drift-Corrected Timer Architecture

Browser timers using setInterval can accumulate drift over long periods because JavaScript is single-threaded and intervals may fire later than scheduled. This timer implements drift correction by comparing actual elapsed time against expected elapsed time on each tick, then adjusting the next interval to compensate. The result is accuracy within a few milliseconds over a full 25-minute session, which is more reliable than naive setInterval implementations that can drift by several seconds over the same period.

Estimation Calibration

The task tracking feature helps calibrate your estimation accuracy over time. Research on the "planning fallacy" by Daniel Kahneman and Amos Tversky shows that people consistently underestimate task duration by 25-50%. By tracking estimated versus actual pomodoros for each task, you can identify your personal bias factor and adjust future estimates accordingly. This leads to more realistic project planning and reduced schedule overruns.

Why Use This Tool

Designed for Deep Work

This timer is built to eliminate friction from your focus routine. The circular progress ring provides a glanceable visual of time remaining without requiring you to read numbers. Session types are color-coded (green for work, emerald for short breaks, blue for long breaks) so you always know your current state at a glance. Desktop notifications and an audible beep alert you when sessions end, so you can stay in your editor or document without watching the timer.

Runs 100% in Your Browser

Everything runs client-side. Your tasks, settings, and session history are stored in localStorage and never leave your device. Sound alerts use the Web Audio API to generate tones directly in the browser with zero audio file downloads. The timer works fully offline after the initial page load, making it suitable for airplane mode or restricted network environments.

Keyboard-First Workflow

Power users can control the entire timer without reaching for the mouse. Press Space to start and pause, R to reset the current session, and S to skip to the next session. Task input supports Enter to add. These shortcuts keep your hands on the keyboard where they belong during focused work sessions.

FAQ

What is the Pomodoro Technique and how does this timer implement it?

The Pomodoro Technique is a time management method developed by Francesco Cirillo in the late 1980s. It uses a kitchen timer to break work into 25-minute focused intervals called pomodoros, separated by 5-minute short breaks. After four pomodoros, you take a longer 15-minute break. This timer automates the full cycle, tracking sessions and transitioning between work and break periods automatically.

Can I customize the work and break durations?

Yes. Open the Settings panel to adjust work duration (1-120 minutes), short break duration (1-30 minutes), and long break duration (1-60 minutes). Your custom durations are saved in localStorage and persist across browser sessions. The default values follow the classic Pomodoro Technique: 25 minutes work, 5 minutes short break, 15 minutes long break.

How does the task tracking with estimated pomodoros work?

Each task can have an estimated number of pomodoros needed to complete it. As you work through sessions, actual pomodoros are tracked against estimates. This helps you calibrate future estimates and understand how long tasks really take. Tasks persist in localStorage so your list survives page refreshes.

Will I get notified when a session ends if the tab is in the background?

Yes. When you grant notification permission, the timer sends a desktop notification with an audible beep when each work or break session ends. The browser tab title also updates with the remaining time, so you can monitor progress from your taskbar without switching tabs.

Does the timer keep running if I close my browser?

No. The timer uses setInterval for real-time countdown and will pause if you close the browser tab. However, it does continue running when the tab is in the background or minimized. Your task list and settings are saved in localStorage and will persist across sessions.