CPR Compression Rate Metronome
A 100 to 120 beats per minute practice metronome with 30:2 cycle timing, rescuer switch prompts and depth reminders.
About this tool
CPR Compression Rate Metronome
A 100 to 120 beats per minute practice metronome with 30:2 cycle timing, rescuer switch prompts and depth reminders.
The CPR Compression Rate Metronome paces chest compressions at the 100 to 120 per minute specified in the American Heart Association 2020 and European Resuscitation Council 2021 guidelines, with an audible click, a visual beat and a running compression count. It also times the full cycle — 30:2 for adults, 15:2 for two-rescuer paediatric CPR — shows the resulting chest compression fraction against the 60% target, and counts down to the two-minute rescuer swap. It is a practice aid for training, not an emergency tool.
How to use CPR Compression Rate Metronome
- 1
Open CPR Compression Rate Metronome on AltFTool — it loads instantly in your browser.
- 2
Drag the "Compression rate" slider or tap the 100 /min, 110 /min or 120 /min preset, then choose who you are practising on — Adult, Child or Infant, one or two rescuers.
- 3
Enter "Pause for two breaths (seconds)" and "Swap rescuer every (minutes)", tick Audible click, then press Start.
- 4
Follow the beat circle's compression count, read the Chest compression fraction row against the 60% target, and press Copy result to save the pacing settings.
Why use CPR Compression Rate Metronome
Guideline rate, not a guess
Locked to the published 100–120 per minute window with a warning outside it.
Whole-cycle timing
Counts the compression phase and the ventilation pause, and reports the compression fraction.
Swap prompt built in
A countdown to the two-minute changeover, which is where compression quality usually slips.
Common use cases
- Practise on a manikin at a steady 110 per minute instead of drifting faster as adrenaline rises.
- Learn how long 30 compressions actually take and how quickly a ten-second breath pause eats the compression fraction.
- Rehearse two-rescuer 15:2 paediatric timing before a BLS assessment.
- Feel the two-minute rescuer swap interval so the changeover becomes automatic.
Frequently asked questions
What is the correct CPR compression rate?
100 to 120 compressions per minute for adults, children and infants, per both the AHA 2020 and ERC 2021 guidelines. Going faster does not help, because the chest needs to recoil fully between compressions for the heart to refill — rates above 120 measurably reduce the volume pumped.
How deep should chest compressions be?
For an adult, at least 5 cm and no more than 6 cm. For a child, about one third of the chest depth, roughly 5 cm; for an infant, about one third of the chest depth, roughly 4 cm, using two fingers or the two-thumb encircling technique.
How many compressions before rescue breaths?
Thirty compressions to two breaths for adults, and for children and infants when there is only one rescuer. With two trained rescuers on a child or infant the ratio changes to 15:2. Once an advanced airway is in place, compressions become continuous with one breath every 6 seconds.
How often should rescuers swap during CPR?
About every two minutes, which is roughly five cycles of 30:2 at 110 compressions per minute. Compression depth and rate degrade measurably before the rescuer feels tired, so the swap is timed rather than judged, and it should take under 10 seconds.