Live demoGlobal timer
Timer demo
A single global countdown, synced across every browser.
Anyone can control it — open a second tab and watch them stay locked together.
Or scan the QR code to open it on your phone and watch it stay in sync.
Timer
0.00
Seconds
Syncing clock…
How it works
01
One Redis key holds the current anchor: server time, value, and rate. No rooms — it's a single global clock.
02
Every control (reset, pause/resume, speed) re-anchors on the server, then broadcasts the new anchor over Redis pub/sub.
03
Each browser syncs to server time with an NTP-style clock, then evaluates the anchor locally every frame — no value streaming.
04
Evaluation is deterministic — every client computes the same value for a given server moment. After clock sync, clients typically agree within ~30ms.