What problem this solves
A rug that’s too small is the most common living-room mistake. The standard interior design rule is “the rug should hold the front legs of the major furniture” — but that rule depends on the arrangement. A floating sectional in a small room needs a rug that fits under all four legs; a sofa-against-the-wall arrangement only needs the front legs on the rug; a bedroom needs the rug under the bottom two-thirds of the bed plus 50 cm on each side. The same primary furniture (a 220 cm sofa) gets a different rug size depending on which rule applies.
This calculator outputs standard stock rug sizes (which are dramatically cheaper than custom) and tells you which arrangement your room actually has — so you stop buying rugs that don’t fit your layout.
Who it’s for
- Living room designers picking the right size rug before the client orders online
- Bedroom designers placing an under-bed rug that doesn’t disappear
- Dining room designers sizing a rug that holds chairs pulled out (often the biggest sizing mistake)
- Homeowners buying their first rug and unsure what size to commit to
Why dining rooms have their own rule
A dining rug needs to be wider than the table by 60 cm on each side so a chair can be pulled out without catching on the rug edge. A 6-seat table is 200 × 90 cm; the rug therefore needs to be at least 320 × 210 cm. Most stock dining rugs come in 240 × 300 or 270 × 360 sizes — the calculator picks the right stock size based on table dimensions, not a generic recommendation.
Limitations
- Stock sizes assumed at 60 cm increments; off-stock sizes exist but cost more.
- Round rugs are popular but sizing math differs — diameter should be ≥ the longest furniture dimension.
- Layered rugs (small on large) not modelled.
- Open-plan rooms may need two rugs; the calculator handles one zone at a time.
- Round dining tables need a round rug sized to the table + 60 cm.
Practical rules of thumb
Living room: sofa length + 60 cm for the rug length (gives 30 cm border each end); seating-to-coffee-table distance + 90 cm for the rug width. Bedroom: bed width + 60 cm for rug width (30 cm each side); bed length × 2/3 + 30 cm for rug length (so the rug sits under the bottom two-thirds). Dining: table + 120 cm each direction. Entryway: leave 15–20 cm of bare floor around the rug so the door can clear it.