Crib Dimensions
A standard full-size crib, the regular size, is 28 in (71 cm) wide and 52 3/8 in (133 cm) long inside, with a tolerance of 5/8 in, and takes a mattress at least 27 1/4 × 51 5/8 in (69 × 131 cm) and no more than 6 in thick. Outside, most cribs measure about 29–31 in wide, 53–57 in long and 35–45 in tall. These sizes are fixed by US safety rules (16 CFR 1219), so any full-size crib mattress fits any full-size crib. Mini cribs are smaller and have no single standard.
Crib dimensions chart
| Compared | Full-size crib | Mini crib (typical) |
|---|---|---|
| Inside width | 28 ± 5/8 in (71 cm) | about 24 in (61 cm) |
| Inside length | 52 3/8 ± 5/8 in (133 cm) | about 38 in (97 cm) |
| Mattress | at least 27 1/4 × 51 5/8 in, max 6 in thick | about 24 × 38 in, 3–5 in thick |
| Outside size | about 30 × 54–57 in | about 26 × 40 in |
| Height | 35–45 in | 33–40 in |
| Floor space with clearance | about 4 × 6 ft | about 3 × 5 ft |
European cots use different mattresses, usually 60 × 120 cm or 70 × 140 cm. A crib mattress also fits most toddler beds, which is why toddler bed dimensions are about the same as the crib's.
Safety measurements
The rules for cribs sold in the US set these limits; use them to check an old crib too:
| Measurement | Rule |
|---|---|
| Space between slats | 2 3/8 in (6 cm) or less |
| Gap between mattress and crib side | No more than two fingers |
| Rail height above the mattress support, lowest position | at least 26 in (66 cm) |
| Corner posts | No more than 1/16 in above the end panels |
| Drop sides | Not allowed since 2011 |
Lower the mattress before the baby can sit up, and again before they can stand. Stop using a crib when the child is 35 in (89 cm) tall or can climb out.
Space in the nursery
Leave about 2 ft (60 cm) of clear floor on the side you lift the baby from, and keep the crib away from windows, blinds and their cords, heaters and shelves a child could reach. A full-size crib with that clearance needs about 4 × 6 ft of floor.
Building nursery furniture
We do not offer crib plans: a crib must meet safety standards that a home build cannot easily prove, so buy a certified one. The furniture around it is a good project, built from plywood or MDF with a child-safe finish:
Frequently asked questions
What are standard crib dimensions?
Inside, a full-size crib is 28 ± 5/8 in wide and 52 3/8 ± 5/8 in long (71 × 133 cm), the size set by US safety rules. Outside, most cribs are about 29–31 in wide, 53–57 in long and 35–45 in tall.
What size is a crib mattress?
A full-size crib mattress is at least 27 1/4 × 51 5/8 in (69 × 131 cm) and no more than 6 in (15 cm) thick. In Europe, cot mattresses are usually 60 × 120 or 70 × 140 cm.
What are mini crib dimensions?
There is no single standard: most mini cribs take a 24 × 38 in mattress, 3–5 in thick, and measure about 26 × 40 in outside. Buy the mattress the crib maker specifies.
How far apart can crib slats be?
No more than 2 3/8 in (6 cm), about the width of a soda can, so a baby's body cannot slip through.