CPR timer app
A CPR timer built to be read across the resus bay
A 2-minute CPR cycle timer with digits big enough to be seen by the whole team, audible warnings before each rhythm check, and a clock that does not drift when the screen locks. Designed for the resus trolley, not the wrist.
What you get
- Drift-free 2-minute countdownUses the monotonic device clock. Stays accurate to the second across a 20-minute arrest even with the screen off or the tab backgrounded.
- Bay-readable typographyDigits fill the screen on a phone, tablet, or cast monitor. Visible from across a resus bay without anyone leaning in.
- Optional 10-second warning toneA short tone at -10 seconds and a longer one at 0:00 cues the team leader to call the rhythm check. Easy to mute when not wanted.
- Tap-to-pause rhythm checkPause the cycle when you stop compressions for the rhythm check; resume on next compression. Pause windows are excluded from total downtime.
Why a phone stopwatch is not a CPR timer
A generic stopwatch counts up and demands mental arithmetic. The scribe has to remember when the cycle started, add two minutes, and call the rhythm check at the right moment — all while also writing on a paper template. In a real arrest this is the first thing that slips.
A dedicated CPR timer counts down each 2-minute cycle, announces the next rhythm check, and restarts itself automatically. The team leader only has to look at one number. Everything else — elapsed time, cycle count, time of last shock — is derived from the same clock and shown on demand.
Designed around the way the timer is actually used
The clock is glanced at, not stared at. So the digits are sized to be legible from across the bay and the colour shifts in the final 15 seconds to draw the eye without being startling. There is no animation that could be misread as a rhythm.
Controls live below the clock and never on top of it. You cannot accidentally pause the timer by tapping the time. The only actions on the main face are the ones that have to happen during the arrest: start, pause for rhythm check, log shock, log drug, mark ROSC.
What the timer exports at the end
Stop the timer and the export captures the start time, the total downtime, every 2-minute cycle, every pause window, and any events tagged during the arrest. Total downtime is the wall-clock duration minus paused rhythm-check windows, so it matches what would be charted by hand if the scribing were perfect.
Cycle accuracy is preserved to the second. If the coroner or audit team needs the timestamp of the third shock or the fifth dose of adrenaline, it is there in the PDF, computed from the same clock that drove the timer during the arrest.
Frequently asked
- How accurate is the countdown?
- It uses the device's monotonic clock rather than setInterval, so it does not drift even if the tab is backgrounded or the phone is locked. After 20 minutes of CPR the elapsed time is accurate to under one second.
- Can I see it from across the resus bay?
- Yes. The digits scale to fill the viewport and can be read from roughly 4 metres on a phone, further on a tablet. Hold a phone in landscape on the trolley monitor or cast the tab to the wall screen.
- Does it make a sound at the end of each cycle?
- Optional. A single short tone fires at 0:00 and at the 10-second warning. You can mute it from the timer screen — useful in pre-hospital settings where ambient noise is already high.
- What if the rhythm check overruns?
- Tap the cycle clock to pause it during the rhythm and pulse check. Resume with another tap. Paused time is shown separately in the export so total downtime is not inflated.
- Does locking the phone stop the timer?
- No. The timer keeps running in the background and the visible countdown is corrected when the screen unlocks. Wake-lock keeps the display on while the app is foregrounded.
CPR Scribe runs in the browser, installs to your home screen, and works offline. No account needed to start — sign in only if you want to save records.