Timerjar is a countdown you can put on a projector, a laptop, or a phone. Pick a length, press start, and leave the digits where the room can see them. There is no account and no setup. The five minute timer is the one already loaded, because that is the length people ask for when they mean a short break, a warning, or a dough rest.
The buttons under the clock jump it to a common length. Those lengths also have their own pages if you want a link to send. Pomodoro runs work and breaks. The stopwatch counts up. Countdown aims at a clock time, including 3:00 pm. Intervals repeat work and rest.
Space starts and pauses, R resets, and F fills the screen. Classroom mode clears the page down to the digits. The alarm is generated in the browser. A notification fires only if you allow it, and the browser asks only after you click. Timing uses an end timestamp, so a tab in the background does not lose the count. Settings for theme, sound, and volume stay in this browser.
Questions
Which timer should I use?
Use this page for a single countdown. Use Pomodoro for work and breaks, the stopwatch to count up, countdown to aim at a time of day, and the interval timer for repeats.
Does it keep running if I leave the tab?
The end time is saved as a timestamp. When you come back, the digits match the time that is actually left. Browsers may delay the alarm slightly while a tab is hidden.
Is Timerjar free?
Yes. The timers run in your browser. You do not need an account.