# A countdown timer for Mac, Windows, and Linux The same full-featured countdown on every desktop OS, because it runs in the browser: fullscreen display, staged warnings, and remote control — no install. Searching for a timer app by operating system — a Mac timer, a Windows countdown widget, a Linux timer — usually ends in three different apps with three different feature sets, and nothing shared between the machines you actually use. A browser-based timer dissolves the question: MaestroTimer runs identically on macOS, Windows, and Linux because it runs in the browser each already has. One timer, every desktop, and the phone in your pocket as its remote control. ## The same setup on every OS There is one installation step, and it is opening a page. The steps: 1. Create a room and add a timer — name, duration, and wrap-up thresholds for staged warnings as time runs low. 2. Open the room's viewer link in any browser: Safari on the Mac, Edge or Chrome on Windows, Firefox or Chromium on Linux. 3. Go fullscreen — F11 on Windows and Linux, Cmd+Ctrl+F on macOS — for a clean display. 4. Control it from anywhere: the controller view on your phone or a second machine runs the countdown remotely. ## About the widget and menu-bar question Many OS-specific searches want a small always-visible timer — a Mac menu-bar widget, a Windows desktop gadget. Native widgets do that one job well, and if a tiny personal timer is the entire need, a widget is a fine answer. The browser approach trades the widget form for capabilities widgets do not have: a timer visible on several machines at once, staged visual warnings, messages, a [running order](https://maestrotimer.com/articles/run-of-show) of multiple timers, and control from a different device than the one displaying. Keep the viewer in a small browser window beside your work and it serves the glanceable case too. ## Where cross-platform actually matters The OS question disappears exactly when timing gets serious: the presenter has a MacBook, the venue machine runs Windows, the signage box is a Linux kiosk. A browser timer treats them as three screens of the same room — open the viewer on each and all of them stay in sync. The live connections view lists each connected machine, and count-up mode, linked timers, and scheduled starts work identically everywhere, because there is only one implementation: the page. ## FAQ ### Is there a countdown timer for Mac without installing an app? Yes — open the timer's viewer link in Safari or any browser and go fullscreen with Cmd+Ctrl+F. Nothing is installed, and the same link works on every other OS. ### Does the timer work the same on Windows and Linux? Identically. It runs in the browser, so macOS, Windows, and Linux display the same timer with the same features — F11 gives fullscreen on both. ### Can one timer show on machines with different operating systems? Yes. Every machine opens the same viewer link and stays in sync, because they all display the same room. ### Does it work offline? No — it is a web app and needs an internet connection. The trade is that nothing is installed and every OS is covered by the same page. **One timer for every machine you own** — MaestroTimer runs in the browser: the same countdown on Mac, Windows, and Linux, fullscreen on any of them, controlled from your phone. Staged warnings, messages, and a live connections view built in. [Try MaestroTimer](https://maestrotimer.com)