How to use the rug size calculator
- Choose where the rug will go: living room, under a dining table or under a bed.
- Living room: enter the room size and the bare floor you want along the walls. Dining table: enter the table size and how far past the edge you want the rug. Bed: pick the bed size and how far the rug extends past the sides and the foot.
- Read the minimum or maximum size in feet and inches and the nearest common rug size.
- Tape the outline on the floor with painter's tape before you buy.
Formula
Living room: rug size = room size - 2 x wall gap, then the largest common size inside it
Dining table: rug size = table size + 2 x extra on each side
Bed: width = bed width + 2 x side extra; length = bed length + foot extra
Common sizes (ft): 2x3, 3x5, 4x6, 5x8, 6x9, 8x10, 9x12, 10x14, 12x15
The margins are design guidelines, not rules. The default of 24 inches past a dining table lets chairs slide out while staying on the rug. The bed values assume the rug starts at the headboard end.
Worked example
A living room measures 16 by 12 feet. Leaving 18 inches of bare floor on every wall, the biggest rug is 108 by 156 inches (9 by 13 feet). The largest common size that fits is 9 x 12 ft.
A dining table of 72 by 36 inches with 24 inches on each side needs at least 84 by 120 inches (7 by 10 feet), so the smallest common size that covers it is 8 x 10 ft.
A queen bed is 60 by 80 inches. With 24 inches on each side and 24 at the foot, the rug must cover 108 by 104 inches, so a 9 x 12 ft rug works.
Choosing by room type
In a dining room the rug should be big enough that the back legs of the chairs stay on it when pulled out, which is why you add space on every side of the table. If a chair leg catches on the edge, the rug is too small.
In a living room, a rug that is too small looks like a postage stamp. A good rule is for at least the front legs of the sofa and chairs to sit on the rug. In a bedroom, the rug can sit under the lower two thirds of the bed or fully under it, with a border on both sides.
Checks before you buy
A few quick checks save a return.
- Outline the rug with painter's tape and walk around it. Check that doors still swing over it.
- Allow a rug pad. It adds a little to the size and keeps the rug from sliding.
- Round or runner rugs follow different rules. Use the square footage of the shape you want.
- Rugs are sold in nominal sizes, and the actual size can be a few inches different.
Assumptions and limits
- The common sizes are 2 x 3, 3 x 5, 4 x 6, 5 x 8, 6 x 9, 8 x 10, 9 x 12, 10 x 14 and 12 x 15 feet, in either direction.
- Margins are your own choices. The defaults are common design guidance and not code.
- Rooms are rectangles. Furniture other than the table or bed is not considered.
- The bed layout assumes the headboard is against a wall and the rug starts there.
Frequently asked questions
What size rug do I need under a dining table?
Add 24 to 30 inches to every side of the table so the chairs stay on the rug when pulled out. A 72 by 36 inch table with 24 inches each side needs at least 7 by 10 feet, so an 8 by 10 rug is the usual choice.
What size rug goes under a queen bed?
An 8 by 10 or 9 by 12 foot rug is common. With 24 inches to each side and foot, a queen bed needs about 9 by 8.7 feet, which makes 9 by 12 the nearest standard size.
How much floor should show around a living room rug?
Many designers leave 12 to 24 inches of bare floor along each wall. Pick what looks right in your room, and enter it in the form to see what fits.
Should the sofa sit on the rug?
At least the front legs of the sofa and chairs should rest on it so the seating group looks connected. Check this by taping the outline before you buy.