The recommended compression depth for a child during CPR is about 2 inches (5 cm), which corresponds to roughly one-third the depth of the chest from front to back. This applies to children from age 1 through puberty. For infants under 1 year old, the target is about 1.5 inches (4 cm), still following that same one-third rule.
How “Child” Is Defined in CPR
CPR guidelines split pediatric patients into two groups: infants (birth to about 1 year old) and children (age 1 through puberty). Puberty is the dividing line between child and adult protocols. Once someone shows signs of puberty, adult CPR guidelines apply, which call for a compression depth of at least 2 inches but allow for deeper compressions that would be excessive in a smaller child.
The One-Third Rule
Rather than a single fixed number, the American Heart Association uses a proportional guideline: compress at least one-third the front-to-back diameter of the chest. For most children, that works out to about 2 inches. For infants, it’s about 1.5 inches. This ratio-based approach accounts for the wide range of body sizes you’ll encounter, from a toddler to an 11-year-old.
That said, research has raised questions about whether compressing a full one-third of chest depth in children may actually be proportionally more forceful than the equivalent adult guideline. A study using CT imaging found that one-third depth in children represented a higher compression ratio than the standard 2-inch (roughly 50% of chest depth) target in adults. The practical takeaway: push hard enough to reach about 2 inches, but don’t go significantly deeper, because excessive force carries real risks.
Why Depth Matters
Compressions that are too shallow won’t generate enough pressure to push blood out of the heart and into the brain and organs. Compressions that are too deep can cause serious injuries, including rib or sternum fractures, lung damage, and in rare cases, injury to the liver, spleen, or heart itself. Studies have confirmed that rescuers who compress too deeply cause more internal organ injuries than those who stay closer to the recommended range. Hitting that 2-inch target consistently is one of the most important factors in effective CPR.
Compression Rate and Rhythm
Along with depth, aim for a rate of 100 to 120 compressions per minute. That’s roughly the tempo of the song “Stayin’ Alive.” Maintaining this pace alongside the correct depth is what defines high-quality CPR.
If you’re the only rescuer, perform 30 compressions followed by 2 rescue breaths, then repeat. If a second rescuer is available, switch to 15 compressions followed by 2 breaths. The shorter cycle with two rescuers allows more frequent breaths, which is especially important for children since pediatric cardiac arrest is more commonly caused by breathing problems than by heart rhythm issues.
Hand Placement and Technique
For a child, place the heel of one hand on the center of the chest, right on the breastbone between the nipples. For larger children, you can place your second hand on top with fingers interlaced, just as you would for an adult. For smaller children, one hand alone is sufficient.
Research from the 2025 AHA guidelines found that two-handed compressions produced greater depth, while one-handed compressions made it easier to stay at the correct rate. Neither technique has been shown to produce better survival outcomes, so use whichever method lets you consistently reach about 2 inches without going too deep. If one hand isn’t generating enough depth, switch to two.
For infants, the technique is different. The 2025 guidelines now recommend using two thumbs with hands encircling the chest, or a one-hand technique. The older two-finger method has been dropped because it was less effective at reaching proper depth.
Let the Chest Fully Recoil
Between each compression, let the chest come all the way back up to its resting position. This step is easy to overlook when you’re focused on pushing hard and fast, but it’s critical. When the chest rebounds fully, it creates a slight suction effect inside the chest cavity that draws blood back into the heart. Without that refill, the next compression pumps less blood.
Even slight leaning on the chest between compressions reduces this effect. Animal studies have shown that keeping just 10% to 20% of your weight on the chest between compressions significantly decreases the amount of blood the heart pumps. Lift your hands slightly (or at least fully release pressure) after each compression while keeping them in contact with the chest so you don’t lose your hand position.
Quick Reference by Age
- Infant (under 1 year): About 1.5 inches deep, two-thumb or one-hand technique, 100 to 120 compressions per minute
- Child (age 1 to puberty): About 2 inches deep, one or two hands on the breastbone, 100 to 120 compressions per minute
- Adult (puberty and older): At least 2 inches deep (up to 2.4 inches), two hands, 100 to 120 compressions per minute
Single rescuer ratio for all pediatric patients is 30 compressions to 2 breaths. With two rescuers, switch to 15 compressions to 2 breaths.