Four minutes is a black tea steep, a short mobility set, or the awkward gap before a meeting that started late. It is long enough to clear a sink and short enough that you should not open a new project.
On a projector, four minutes reads as a warning. Tell the room what happens when it hits zero. Press space to start or pause, R to reset, and F for fullscreen. The screen can stay awake after you start, using the wake lock your browser allows. Pick the alarm before you begin. A bell, a chime, a beep, or a short digital pulse all come from the Web Audio API, so there is no sound file to wait on.
This page is the 4 minutes countdown and nothing else is running underneath it. Related lengths are linked under the guide if you want a neighbor, and the timer itself stays above the fold.
Questions
How do I run a 4 minutes timer on a projector?
Press start, then F or the fullscreen button. Classroom mode hides the writing so the digits fill the wall. On a projector, four minutes reads as a warning. Tell the room what happens when it hits zero.
What is 4 minutes actually good for?
Four minutes is a black tea steep, a short mobility set, or the awkward gap before a meeting that started late.
Will the countdown drift if I switch tabs?
No. The end is a timestamp. The display is the gap between that timestamp and now, so a background tab does not lose seconds the way a ticking counter would.