In a real emergency, call your local emergency number first (911 in the US, 112 in Europe, 999 in the UK). The dispatcher will talk you through CPR. This page is a timing aid for training and practice.
Why 110 beats per minute
Current guidelines from the American Heart Association and the European Resuscitation Council ask for chest compressions at 100 to 120 per minute. 110 sits in the middle, so you stay in range even if you drift a little faster or slower. Use the 100 and 120 buttons to feel the edges of the range.
What the guidelines say about compressions
- Push hard and fast in the centre of the chest, on the lower half of the breastbone.
- For adults, press down at least 5 cm (2 inches), and no more than 6 cm.
- Let the chest come all the way back up between compressions.
- Keep interruptions as short as possible.
A first aid course teaches this properly and lets you practise on a manikin. Many are free or cheap through the Red Cross, Red Crescent or your local ambulance service.
Songs at the right tempo
Trainers often suggest humming a song at about 100 to 120 BPM. The classic is "Stayin' Alive" by the Bee Gees, at roughly 104 BPM. Any song you can tap at 100 to 120 works just as well.
Questions
Will the click keep going if my screen turns off?
Keep the screen on. iPhones in particular pause web audio when the screen locks.
Why is there no sound on my iPhone?
Check the ring/silent switch. In silent mode Safari mutes web audio.