Regular Crib Mattress Size

Crib Mattress Size

• A standard crib mattress is 27-1/4 inches wide and 51-5/8 inches long and will fit most standard-size cribs. However, there are slight variations in crib mattress sizes and in crib sizes. These variations --- even as small as ¼ inch, are critical to infant safety.

The Finger Test

• The crib mattress must fit the crib so it is snug against the crib sides or rails to prevent the baby from sliding under the mattress and between the mattress and crib sides and suffocating. Put the mattress in the crib in the store and try to slip two fingers between the side of the mattress and the side of the crib. If you can do this, the mattress is too small for the crib and dangerous for you baby. You should be able to slip only one finger between the mattress and the crib sides. Perform this test even if the mattress comes with the crib or the salesperson tells you the mattress is the correct size for the crib.

Foam Versus Innerspring

• Crib mattresses come in foam and innerspring styles. From the safety point of view, either is fine. The point to keep in mind is that a crib mattress must not be more than 6 inches deep, and one less than 4 inches deep may not provide the support and comfort you want for your infant.

Soft Versus Firm

• A crib mattress can be soft, medium or firm. Firm mattresses are recommended because they provide the best support for your infant and the least chance that a very young infant will get stuck face down against the mattress. If the mattress feels comfortable to you, it is too soft for an infant.

Standards

• Crib mattresses must meet safety standards of the Consumer Product Safety Commission and the American Society for Testing and Materials. Check for labels that verify the mattress meets those standards. Mattresses made of organic materials are certified according to the Global Organic Textile Standard. The largest certifier in the United States is Oregon Tilth.