Forty-five minutes is a common class period and workshop-session length. Start it here and put it on the projector — every phone in the room can pull up the same link.
00servers to run this
Anyone opening your link right now sees exactly this.
Change the countdown
Already running at 45 minutes above — adjust it here if you need something else.
Count-up starts from zero the moment you press start — like a shared stopwatch. No duration to set.
Generated on demand by a third-party QR API (goqr.me) — the only feature on this site that makes an external request. See Privacy.
Common questions
Is 45 minutes a common class-period length this suits?
Yes — it's one of the most common school class-period lengths, which is why it's offered as a quick-timer preset alongside custom durations.
Can students follow the countdown on their own phones too?
Yes — share the link and any device can open it; the projector and every phone will show the identical time remaining.
Does the timer keep going if the projector or Wi-Fi drops?
Yes, on any device that already has the page open — since the countdown is calculated locally against a timestamp in the URL, it doesn't need an ongoing connection to keep counting.