Crib Safety for Newborns | Rules That Keep Babies Safe

For the full breakdown, see our best Cribs for Newborns guide.

When a newborn comes home, the crib is the room’s most important safety check. The CPSC’s requirements for crib safety for newborns cover three layers: the crib’s construction and dimensions, the mattress fit, and what goes inside. Each layer is straightforward to get right, and this article covers the exact rules plus the mistakes most parents encounter.

What CPSC Standards Apply to Newborn Cribs?

Every full-size crib manufactured after June 28, 2011 must meet CPSC mandatory standard 16 CFR 1219, which adopts ASTM F1169-25. The standard specifies exact dimensions and construction rules to prevent entrapment, falls, and suffocation. The table below lists every critical measurement and requirement.

Always check the CPSC’s crib safety guidelines for the current recall list before using any crib that isn’t brand-new.

Newborn Crib Safety: Mattress and Bedding Setup Rules

The mattress must be firm — it should spring back when pushed and not indent at all. Use only a tight-fitting crib sheet made for that mattress size, and remove the plastic wrapping from a new mattress before use, as plastic is a suffocation hazard.

Run the two-finger test: slide two fingers between the mattress and the crib side. If more than two fit, the mattress is too small and needs replacement with one that matches the crib’s exact dimensions.

Place the baby on their back for every sleep — naps and nighttime. The crib should be empty: no pillows, quilts, stuffed toys, or bumper pads. Use a wearable sleeper instead of a blanket. If you do use a thin blanket, tuck it around the mattress only as high as the baby’s chest and position the baby’s feet at the foot of the crib — this is called foot-to-foot positioning. Remove bibs or necklaces before placing a baby in the crib, and take down the mobile when the baby can push up on hands and knees or by 5 months, whichever comes first.

Common Mistakes That Compromise Crib Safety

The most dangerous crib errors — using a drop-side crib, leaving a gap wider than two fingers, and placing soft objects in the sleep space — are also the most preventable. Each has a clear fix.

If you have one, replace it immediately. A mattress gap wider than two fingers can trap an arm or leg — test it and exchange the mattress if it fails. Bumper pads, pillows, and stuffed toys add suffocation and strangulation risk to every sleep. The only safe crib contains a baby, a fitted sheet, and nothing else.

Pre-1978 cribs likely contain lead paint. If the crib is that old, strip and repaint it with lead-free paint or discard it. Keep the crib away from windows and drapes — blind cords are a strangulation hazard. And never let a baby sleep on a couch or adult bed:

Crib safety for newborns is simple to verify: check the slats, test the mattress gap, feel the mattress firmness, and confirm the crib is empty except for the fitted sheet. Once your crib passes those checks, our roundup of the best cribs for newborns covers tested, CPSC-compliant options that make setup even easier.