Rug Size Calculator Leave an Even Border, Then Buy the Size Below
Enter the room dimensions and how much floor you want to keep showing. You get the largest stocked rug that fits.
Too Small Is the Usual Mistake
A rug that floats in the middle of the floor makes a room look smaller, not larger.
Rugs Come in Fixed Sizes
There is no 273 cm rug. The answer is always a size someone actually sells.
What size rug do I need?
At a Glance
Leave an even border of bare floor around the rug — about 45 cm (18 in) is the usual choice — then take the largest standard size that still fits inside what is left. In a 5 × 4 m room that gives you 410 × 310 cm to play with, and the rug to buy is 400 × 300 cm. In a 16 × 13 ft room it works out at 12 × 9 ft (144 × 108 in).
Almost every rug-sizing rule reduces to the same thing: how much floor stays visible. A wider border reads as a deliberate frame and makes the room feel larger; a narrow one makes the space feel enclosed and warm. What does not work is a border that varies — a rug 20 cm from one wall and 80 cm from the other looks like a mistake, because it is.
| Border | Metric | Imperial | Effect |
|---|---|---|---|
| Snug | 30 cm | 12 in | Cosy; suits small rooms and hallways |
| Standard | 45 cm | 18 in | The default for a living room |
| Generous | 60 cm | 24 in | Airy; suits large or open-plan rooms |
The second half of the job is that rugs come in fixed sizes. European shops stock roughly 120 × 80, 170 × 120, 200 × 140, 230 × 160, 290 × 200, 340 × 240 and 400 × 300 cm; US shops sell 3 × 5, 4 × 6, 5 × 8, 6 × 9, 8 × 10, 9 × 12, 10 × 14 and 12 × 15 ft. The calculator picks the largest of those that fits, which is why the answer jumps in steps rather than sliding.
available = room side − 2 × border, then take the largest stocked size that fitsThese are the values the calculator loads by default.
Convert the room to the rug's unit
5 × 4 m is 500 × 400 cm.
Subtract the border twice
A 45 cm border on both sides takes 90 cm off each dimension: 410 × 310 cm left.
Find the largest size that fits
400 × 300 cm fits inside 410 × 310, and it is the biggest stocked size that does. The next one down, 340 × 240, would also fit but leaves 80 cm of floor on each side.
Lay the long side along the long wall
The rug's 400 cm side runs along the 5 m wall, leaving 50 cm at each end and 50 cm at each side.
The size is the starting point; where the furniture sits decides whether it works.
All legs on, or front legs on. The two arrangements that look intentional are a rug large enough for every piece of furniture to stand on it, or one where the front legs of the sofa and chairs sit on the rug and the back legs are off. Furniture standing entirely off the rug is the arrangement to avoid — it cuts the seating area in two.
Dining rooms are sized from the table, not the room. The rug has to extend far enough past the table that chairs stay on it when pushed back — about 60 cm (24 in) on every side of the table. Measure the table, add 120 cm to each dimension, and use that instead of the room.
Bedrooms want the rug under the bed. Run it from about a third of the way up the bed to well past the foot, so your feet land on it when you get up. It should extend around 60 cm (24 in) beyond each side of the bed.
Nothing shown? No stocked size leaves the border you asked for. Choose a snugger border, or accept a small accent rug placed deliberately rather than centred.
For what goes underneath, see the Flooring Calculator.
A rectangular room, a rectangular rug
The calculation assumes a rectangular room with the rug centred in it, and it works from the room rather than from the furniture. Dining rooms and bedrooms are sized from the table or the bed instead — see the notes above.
Standard sizes vary a little between retailers and between markets, and some sell nominal sizes that are a few centimetres off the label. Check the actual dimensions before buying, especially near a size boundary. Round, runner and freeform rugs follow different conventions entirely; a runner is chosen by hallway width, leaving roughly 10 cm of floor on each side.