What is the Standard Crib Mattress Size?

Crib Mattress Size and Dimensions
Size Tape Measure

The Federal government regulates the size for all standard crib mattresses via the Consumer Product Safety Improvement Act of 2008 (CPSIA).

The minimum size is 27 1/4” x 51 5/8” with a thickness not exceeding 6 inches.

Here’s where things get a bit wonky: There’s no such thing as a “universal fit” because while crib sizes are also regulated, their interior dimensions have a “plus or minus” tolerance from the standard 28” x 52 3/8” rectangle.

Snug = Safe

The goal is to have the crib mattress fit either very snug or moderately snug in the crib. A good rule of thumb is that no more than two fingers of space should exist between the side of the mattress and the crib frame. Any more than that, the crib mattress is too small and could be a suffocation and entrapment hazard.

Safety is Priority #1

Colgate not only meets, but exceeds all government safety standards and we were instrumental in establishing additional, voluntary industry standards to keep babies safe. We take great pride in our craftsmanship and exacting manufacturing standards that have produced the world’s best crib mattresses since 1955.

Read More About Crib Mattress Safety:
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