Rug Size Calculator: What Size Rug Do You Need?

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This rug size calculator tells you which standard rug fits your living room, dining table, bed or hallway. Enter a couple of measurements and you’ll get the best size, a smaller backup, and how much floor will show around the edges.

Most rug mistakes come down to one thing. The rug is too small.

It floats in the middle of the room, the furniture doesn’t touch it, and the whole space looks a bit off. Five minutes with a tape measure fixes that.

Use the Rug Size Calculator

Choose the room first. The boxes change to match: room size for a living room, table size for a dining room, bed size for a bedroom, and hall size for a runner. You can switch to meters and centimeters too.

How the Rug Size Calculator Picks a Size

It’s simple math built on the spacing rules designers use. We didn’t make these numbers up. They come from This Old House and Ruggable, and you’ll see each rule in the sections below.

The rug size calculator checks your space against 10 standard rectangle sizes: 2′ x 3′, 3′ x 5′, 4′ x 6′, 5′ x 7′, 5′ x 8′, 6′ x 9′, 8′ x 10′, 9′ x 12′, 10′ x 14′ and 12′ x 15′. Round rugs come in 6′ and 8′, and runners from 2′ x 5′ up to 2.5′ x 12′.

It turns the rug both ways to find the best fit, so you don’t need to work out which side faces which wall.

One honest limit: sizes vary by brand. A rug sold as 5′ x 8′ can really be 5’3″ x 7’6″. Always check the exact size on the product page before you order.

Living Room Rug Size Chart

In a living room, aim for 12–18 inches of bare floor between the rug and the walls, per This Old House. That border frames the rug. Go much tighter and it starts to look like wall-to-wall carpet that didn’t quite fit.

The rug size calculator uses 12 inches as the minimum and picks the biggest standard rug that still leaves that gap. Here’s what that looks like for common room sizes:

Both 10′ x 12′ and 11′ x 13′ rooms land on an 8′ x 10′. Ruggable agrees: its size guide pairs an 8′ x 10′ with an 11′ x 13′ room and a 12–18 inch border.

Quick rule if you don’t have the rug size calculator handy: take 2 to 3 feet off each room measurement. That leaves a 12–18 inch border. Rug Knots uses the same idea with its subtract-3-feet rule.

All legs on, or just the front legs?

With the bigger rug, every sofa and chair sits fully on it. That’s the most pulled-together look, and our favorite if the room allows it.

With the smaller option, only the front legs of the seating rest on the rug. This Old House calls this the medium-rug layout, and it works well in tighter rooms. What doesn’t work is a rug that no furniture touches at all.

Shopping for the sofa too? Our sofa size calculator handles that, and it includes a check for whether the sofa will make it through your front door. If you’ve settled on an 8′ x 10′, our best 8×10 washable rug picks are a good place to start.

What size rug for a sectional?

In a standard living room, an 8′ x 10′ works under most sectionals, with at least the front legs on the rug. That’s the advice in Wayfair‘s sectional rug guide. For a big L-shape or U-shape, run your room size through the rug size calculator and lean toward the bigger result.

Got a big or open-plan room? Don’t size to the walls. Size the rug to the seating area and leave the rest of the floor bare.

Dining Room Rug Size: 24 Inches Past the Table

Dining rugs follow a different rule. People push their chairs back to stand up, and if the back legs catch the edge of the rug every time, it gets old fast.

This Old House says to add 24–30 inches on all sides of the table. The rug size calculator uses 24 inches as the minimum, so you get the smallest rug that keeps the chairs on it. If you have room for the next size up, take it.

Round table? A round rug looks natural under it, but an 8′ round only covers tables up to 48 inches across. Bigger than that, go with a large rectangle or square.

Bedroom Rug Size by Bed

Under a bed, the rug should run 18–24 inches past the sides and the foot, according to This Old House. That’s where your feet land in the morning, which is really the whole point.

You’ve got two ways to do it. Full coverage puts the whole bed on the rug, headboard to foot. The more common way is to slide the rug under the lower two-thirds of the bed and leave the nightstands on bare floor. It needs a smaller rug, so it costs less too. The rug size calculator gives you both sizes.

Mattress sizes are from The Sleep Doctor. Bed frames add a few inches, so if yours has a wide frame or a chunky headboard, pick “Custom” in the rug size calculator and enter the frame size instead.

Hallway Runner Size

For a runner, leave 4–5 inches of floor showing on all sides, per This Old House. So a 36-inch hallway takes a 2-foot-wide runner (a 2′ x 8′ is a common pick), and you need about 38 inches before a 2.5-foot runner fits. Enter your hall width and length in the rug size calculator and it does this math for you.

Common runner sizes include 2′ x 5′, 2′ x 6′, 2′ x 8′, 2.5′ x 7′, 2.5′ x 10′ and 2.5′ x 12′. Lots of brands sell other lengths, so the calculator also shows the largest runner your hall can take. In a very long hall, two runners with a small gap often look better than one that stops well short of the end.

Want something washable? We looked at one in our COSY HOMEER runner rug review, and the brand’s other rugs are covered in our COSY HOMEER review.

Common Rug Size Mistakes

Even with a rug size calculator, these four mistakes catch people out:

• Buying too small. When you’re stuck between two sizes, go bigger, as long as about a foot of floor still shows.
• Centering the rug on the room instead of the furniture. The rug belongs to the seating group, not to the walls.
• Forgetting the door. Check that any door that swings into the room can still clear the rug, especially a thick one.
• Trusting the name of the size. “8×10” is a label. Read the real measurements in the listing.

Need a soft rug for a smaller space like a bathroom? Our thick bath rug guide covers plush picks in small sizes.

Rug Size FAQ

What size rug do I need for a 10×12 room?

An 8′ x 10′. It leaves about 12 inches of floor on every side, which is right at the minimum border. Run your exact measurements through the rug size calculator to see your border.

What size rug fits a 12×15 room?

A 9′ x 12′. It leaves 18 inches of floor all the way around.

What size rug goes under a queen bed?

A 6′ x 9′ under the lower two-thirds of the bed, or an 8′ x 10′ if you want the whole bed on the rug.

What size rug goes under a king bed?

An 8′ x 10′ under the lower two-thirds, or a 9′ x 12′ for full coverage.

Is it better to get a bigger or smaller rug?

Bigger, almost every time. Just keep at least a foot of floor showing around a living room rug.

Does the rug size calculator work in metric?

Yes. Switch the units to meters and centimeters and every result shows centimeters, with each rug size in meters too.

The Bottom Line

Measure once, run the numbers through the rug size calculator, and pick the bigger option when you’re between two sizes. Your room will look finished instead of half-done. For more sizing tools, see our furniture dimensions calculator page.

Sources: This Old House rug sizing guide; Ruggable rug size guide; The Sleep Doctor mattress sizes.