Countdown Timer

WHAT IT DOES

Countdown Timer is a browser extension that displays a floating countdown timer you can set to any duration from seconds to hours. The timer shows remaining time in a large digital display with a visual progress ring that updates in real time, changing color from green to yellow to red as time runs out. You can start, pause, and reset the timer with simple buttons, and the timer plays a pleasant chime sound when time is up. The timer state (remaining time, running status, and duration) persists across page loads, so your timer continues running even if you navigate away or refresh the page. The tool is ideal for productivity techniques like Pomodoro, presentations, cooking, exercise intervals, study sessions, and any task that benefits from timed focus.

WHERE IT RUNS

Countdown Timer runs on any webpage, overlaying a floating panel that does not interfere with page content. It operates entirely in your browser as a lightweight userscript, using JavaScript's setInterval to update the timer every second. It works on any page, whether static or dynamic, with no external dependencies. All timer state is stored locally using GM_setValue—no data is ever sent to any server.

HOW TO USE

After installation, open the floating panel by clicking the extension icon. The timer displays "00:00" with a progress ring. To set a duration, enter a time in the input field using MM:SS format (e.g., "05:30" for 5 minutes 30 seconds) or HH:MM:SS format (e.g., "01:15:00" for 1 hour 15 minutes), then click the Set button. You can also click preset buttons for 1 min, 5 min, 10 min, 15 min, 30 min, or 1 hour. Click the Start button to begin counting down—the progress ring fills clockwise and the remaining time updates every second. Click Pause to pause the timer, and Reset to reset it to the original duration. When the timer reaches zero, a chime sound plays and a flash message appears. The timer state saves automatically, so if you close the page and reopen it, the timer continues from where it left off.

REAL MECHANISM — WHY THIS WORKS

Most browser timers rely on setInterval or setTimeout, which can drift or stop working when the tab is inactive. Countdown Timer uses a different approach: it stores the timer state (remaining seconds and running status) in GM_setValue every second, and automatically restores this state when the page loads or when the extension is reopened. The timer engine uses a simple decrement tick: every second, it subtracts one from the remaining seconds, updates the display and progress ring, and saves the new state. If the tab is backgrounded, the timer may slow down, but the persistence mechanism ensures that when the page is reopened, the timer resumes with the correct remaining time. The progress ring is rendered using an SVG circle with a stroke-dasharray and stroke-dashoffset that is recalculated based on the ratio of remaining time to total duration. The ring color transitions from green (above 50%), to yellow (25-50%), to red (below 25%). The notification sound uses the Web Audio API to generate a simple chime of three sine wave tones at different frequencies, requiring no external audio files. This approach ensures accurate, persistent, and fully private timer functionality without requiring any external services or network access.

THE PANEL

The floating panel is fully draggable and remembers its position per site, snapping to the edges of the viewport when dragged near them. You can collapse the panel to a small icon to minimize screen distraction and expand it back with a single click. The panel is resizable from the bottom-right corner, giving you more space to view the timer and controls. Press the Escape key to close the panel instantly. The panel remains open across page navigation within the same domain, maintaining your current view state. All preferences—panel position and timer state—are saved globally for a seamless experience.

PLEASE NOTE

Countdown Timer requires the free BotGentz extension to be installed and enabled, as it relies on the cross-extension messaging API provided by BotGentz for DOM access permissions. Timer accuracy may vary when the browser tab is backgrounded or the computer is sleeping, as JavaScript timers can be throttled. The persistence mechanism ensures that when the page is reopened, the timer continues with the correct remaining time (based on the last saved state, not elapsed real-time). Sound notifications require audio context to be initialized, which may require user interaction on some browsers. All timer data is stored locally in your browser using GM_setValue. No timer settings, remaining times, or usage data are ever sent to any server. The extension does not read, store, or transmit any personal information. It only calculates and displays timer values locally at your request.