Between 100 and 120 chest compressions per minute is the correct rate for adult CPR in Australia. That is the figure set out in the Australian Resuscitation Council guidelines, published jointly with New Zealand as the ANZCOR guidelines, and it is the number every accredited first aid course in the country trains you to hit.
Below 100 a minute the heart is not squeezed often enough to keep blood moving to the brain; above 120 the chest does not have time to spring back between pushes, so each compression pumps less blood and you tire faster. The target is a steady, almost metronomic two compressions every second.
What the Australian guidelines actually specify
The current ANZCOR Guideline 8 for cardiopulmonary resuscitation, approved in April 2021, makes six recommendations that matter here. Compressions should be given at a rate of approximately 100 to 120 per minute. The compression-to-ventilation ratio is 30:2 for all ages. CPR must start whenever a person is unresponsive and not breathing normally, including occasional gasps. Interruptions to compressions should be minimised. And the sequence every first aider learns is DRS ABCD: check danger, response and send for help, then airway, breathing, CPR and defibrillation.
The companion guideline on compressions adds the practical detail: the heel of the hand goes on the lower half of the sternum, compressions are pushed to about one third of the chest depth, and the chest must be allowed to recoil fully between pushes so the heart can refill.
Why not just compress as fast as you can?
Speed is not the same as output. Blood flow during CPR depends on both how often the heart is squeezed and how completely it refills between squeezes.
- Under 100 per minute — circulation to the brain and heart falls below what is needed, and every second at a slow rate is time without adequate blood flow.
- Around 100 to 120 — the sweet spot where refill and cardiac output are both preserved.
- Over 120 — the chest rebounds incompletely, the heart fills less with each cycle, and arm fatigue builds quickly. ANZCOR notes that compression quality, particularly depth, deteriorates as a rescuer tires and advises changing rescuers about every two minutes where there are enough people, with the swap kept as short as possible. What counts as adequate depth, and why the guideline refuses to cap it, is set out in how deep to push during CPR on an adult.
Research on manikin training consistently shows rescuers drift out of range without noticing — often dropping below 100 within the first couple of minutes — which is why instructors insist on counting out loud.
How to hold the right tempo
In a real emergency you do not have a metronome, so instructors teach a few habits that work under pressure:
- Count out loud. Numbers keep your pace honest and let a second rescuer follow you.
- Think “two per second.” 100 to 120 a minute is almost exactly two pushes every second — a count of one-one-hundred, two-one-hundred works well.
- Use a rhythm if it helps. Many trainers point to a well-known disco track sitting near 100 beats a minute; anything at that tempo keeps you honest.
- Practise on a manikin with feedback. A device that beeps or lights up for correct rate and depth fixes the feel in your arms far better than reading about it.
Does the rate change for children and infants?
No — the recommended rate stays at roughly 100 to 120 compressions per minute for every age. What changes is depth and hand placement. ANZCOR Guideline 6 sets compression depth at about one third of chest depth for all ages, which works out at more than 5 cm for adults, approximately 5 cm for children and about 4 cm for infants. A single rescuer uses one or two hands for a child and two fingers for an infant, and the compression point stays on the lower half of the sternum throughout.
Age affects rescue breaths far more than it affects rate: infants take mouth-to-mouth-and-nose breaths, children get smaller volumes, and the 30:2 ratio still applies. The full set of differences is covered in our guide to CPR on a child or infant in Australia.
Rate only works alongside depth
An accurate 110 per minute at half the required depth will not circulate blood properly. Depth and rate are checked together in every assessment. ANZCOR deliberately sets no upper limit on depth — the guideline states that the risk of compressions that are too shallow outweighs the risk of compressions that are too deep, so when in doubt, push harder. The chest must rise fully between compressions; leaning on the chest between pushes prevents that refill.
Rate, depth, recoil and hand position are all covered together in our breakdown of the compression-to-breath ratio for adult CPR, and the full adult sequence is set out step by step in the steps of CPR for adults.
Where this is taught at ALIT
The rate, depth and 30:2 ratio are the core practical components of HLTAID009 Provide CPR, which runs for 3.5 hours on campus at the West Melbourne campus for $75.00. You practise on manikins until the tempo feels automatic, and the course is assessed on exactly these parameters. If you need full first aid as well as CPR, HLTAID011 Provide First Aid runs for one day at $160.00 and includes CPR within it.
Enrolments for both courses are open — confirm the next start date with ALIT before you book.
Frequently asked questions
What happens if you do CPR too slowly?
Below about 100 compressions a minute, blood flow to the brain and heart drops. That is why instructors correct a slow tempo first — it is the most common error in training.
Can you do CPR too fast?
Yes. Above roughly 120 per minute the chest cannot fully recoil, each compression moves less blood, and you fatigue faster. Fast and shallow is the least effective combination.
Is 100 to 120 compressions per minute the same for everyone?
The rate is the same for adults, children and infants. Depth and hand technique are what change with age — more than 5 cm for adults, around 5 cm for children and about 4 cm for infants.
Do you pause for rescue breaths?
Compressions pause only long enough to deliver two breaths in each cycle of 30 compressions to two breaths. ANZCOR’s recommendation is to keep those interruptions as short as possible and restart compressions immediately after the second breath.
How do you check your speed during a real emergency?
Count out loud and aim for two compressions per second. If a second rescuer is present, swap roles about every two minutes so compression quality does not drop from fatigue, and swap with the shortest possible pause.
Current guideline references: ANZCOR Guideline 8 – Cardiopulmonary Resuscitation (CPR) and ANZCOR Guideline 6 – Compressions, both approved April 2021. Guidelines are updated from time to time, so check with the relevant authority or your trainer for the version current when you are assessed.
No comments yet — start the conversation.