ChartStandard dimensions — nothing to enter.
A Full mattress is 54 × 75 inches — 4 ft 6 in wide by 6 ft 3 in long, or 137 × 191 cm. It needs a room of at least 9 × 9 ft.
| Measurement | Size | Metric or area |
|---|---|---|
| Width | 54 in | 137 cm |
| Length | 75 in | 191 cm |
| In feet | 4 ft 6 in × 6 ft 3 in | — |
| Sleeping surface | 28.1 sq ft | — |
| Smallest room it fits | 9 × 9 ft | 81 sq ft |
| Comfortable room | 11 × 10 ft | 110 sq ft |
| Fitted sheet | 53–54 × 75 in | typical range |
| Flat sheet | 81–85 × 96–100 in | typical range |
| Comforter or duvet | 80–84 × 86–90 in | typical range |
| Pillows | 2 standard (20 × 26 in) | — |
| Rug under the bed | 6 × 9 ft | — |
Room sizes assume 24 in of clear floor down each side and at the foot as a minimum, 36 in to be comfortable. Bedding is not standardized the way mattresses are. Mattress dimensions are fixed, but sheet and comforter cuts vary between manufacturers, so these are the common US retail ranges — check the size on the packaging of the set you are buying.
The mattress itself. A Full is 54 × 75 inches — 4 ft 6 in wide by 6 ft 3 in long, or 137 × 191 cm. It is also sold as a Double. Full and double are two names for the same mattress. It is 16 in wider than a twin but no longer, which is why tall sleepers skip it.
The room it needs. Bed dimensions are only half the question; the floor around the bed is the other half. The rule used across this site is 24 in of clear floor down each side and 24 in at the foot as the minimum you can live with, and 36 in as the figure that fits a nightstand and lets two people pass. For a Full that is 9 × 9 ft at minimum and 11 × 10 ft to be comfortable. Those are the same numbers the mattress size chart uses, because both come from the one rule.
Bedding, and why these are ranges. The fitted sheet is cut to the mattress, so a Full fitted sheet runs 53–54 × 75 in. Everything else is deliberately larger: the flat sheet at 81–85 × 96–100 in and the comforter at 80–84 × 86–90 in have to hang over the sides and the foot, which is why a comforter bought to the mattress size always looks too small on the bed. Bedding is not standardized the way mattresses are. Mattress dimensions are fixed, but sheet and comforter cuts vary between manufacturers, so these are the common US retail ranges — check the size on the packaging of the set you are buying.
How it compares. A Full is 6 in narrower and 5 in shorter than a Queen (54 × 75 in against 60 × 80 in). A Full is 16 in wider and 5 in shorter than a Twin XL (54 × 75 in against 38 × 80 in). Full dimensions for every size sit on the mattress size chart.
Pocket depth still matters. These dimensions describe the mattress footprint, not its height. A fitted sheet also has to clear the mattress depth plus any topper, which is the measurement most often got wrong — the bedding size chart covers the depth bands.
A Full mattress is 54 × 75 inches, which is 4 ft 6 in wide by 6 ft 3 in long. In centimeters that is 137 × 191 cm.
A 9 × 9 ft room (81 sq ft) is the smallest that leaves 24 in down each side and 24 in at the foot. 11 × 10 ft (110 sq ft) is where it stops feeling tight and a nightstand fits on both sides.
It is built for one adult with room to spread, or two at a squeeze. Split across two sleepers, a Full gives each person 27 in of width — a single bed is 38 in for comparison.
Fitted sheet 53–54 × 75 in, flat sheet 81–85 × 96–100 in, comforter or duvet 80–84 × 86–90 in, and 2 standard (20 × 26 in). These are ranges rather than one number because bedding cuts vary by manufacturer, unlike the mattress itself. Sheets are sold by bed name, so buying "Full" is right — the mattress depth is the measurement worth checking on the packaging.
A Full is 6 in narrower and 5 in shorter than a Queen (54 × 75 in against 60 × 80 in). The Queen needs the bigger room: 9 × 9 ft against 9 × 9 ft.
A 6 × 9 ft rug is the size that works in most rooms — it carries the bed and still shows floor on all three walking sides. The exact answer depends on your room, which is what the rug size calculator works out.