Bath Mat Size Calculator

The short answer

Put the mat where you step out, long side along the tub, shower or vanity, and leave at least 2 to 3 in of floor in front of it. Beside a tub, the mat covers at least half to two-thirds of the tub’s length. Outside a shower, size it to the kind of shower: a small stall, a regular shower or a walk-in. At a vanity, choose a mat no longer than the vanity is wide.

Beside a standard 5 ft tub with 30 in of floor in front, that’s a 21 × 34 in mat. Along a 72 in double vanity, a 24 × 72 in runner.

How to measure

1. The fixture: measure the tub’s length along the side you step out of, or the vanity’s width across the front. For a shower, note whether it’s a small stall, a regular shower or a walk-in. For a new vanity, the bathroom vanity size calculator finds the width that fits your wall.
2. The floor in front: measure from the front of the tub, shower or vanity to whatever is across from it: the wall, a cabinet or another fixture.
3. The door: check whether the bathroom door swings over the spot.

How to use the calculator

1. Choose where the mat goes: beside a tub, outside a shower, or at a vanity with one sink or two.
2. Enter the tub’s length or the vanity’s width, or choose the kind of shower.
3. Enter the floor in front, and check the box if the door swings over the spot.
4. Read the result: the size to buy, a plan from above and the standard sizes around it, each labeled Fits, Tight or Doesn’t fit.
5. Save or share it. Copy link keeps your numbers in the address.

How we calculate

The sizes below are as sold, so the actual size on a mat’s label comes first.

• Beside a tub: the mat covers at least half to two-thirds of the tub’s length, long side along the tub, and no more than the tub. The calculator aims for the middle of that range: a 21 × 34 in mat beside a standard 5 ft tub.
• Outside a shower: 17 × 24 in for a small stall, 20 × 30 in or 21 × 34 in for a regular shower, and 24 × 36 in, 24 × 40 in or 30 × 50 in for a walk-in or open shower. The calculator picks the largest of those that leaves enough floor in front.
• At a vanity: a mat no longer than the vanity is wide. On standard vanity widths, that’s 17 × 24 in at a 24 in vanity, 21 × 34 in at a 36 in one and 24 × 40 in at a 48 in one.
• At a double vanity: one runner across both sinks, no longer than the vanity, or one mat in front of each sink.
• The floor in front: at least 2 to 3 in of floor left between the mat and the wall or fixture across from it, so the mat doesn’t bunch up. The calculator asks for 3 in to Fit. Less is Tight, and a mat deeper than the floor doesn’t fit.
• The pick: the best size that Fits; if none does, the Tight one closest to fitting, preferring sizes that leave the margin.

Worked examples

Worked example

Beside a 5 ft tub with 30 in of floor in front

What we know

• Tub: 60 in long
• Floor in front: 30 in

How it works out

1. Beside a 60 in tub, the mat should cover at least half to two-thirds of it, 30 to 40 in, long side along the tub.
2. A 21 × 34 in bath mat leaves 9 in of the 30 in of floor in front.

A 21 × 34 in bath mat.

Worked example

Outside a walk-in shower with 30 in of floor

What we know

• Shower: a walk-in or open shower
• Floor in front: 30 in

How it works out

1. Outside a walk-in or open shower, look for a 24 × 36 in, 24 × 40 in or 30 × 50 in mat.
2. A 24 × 40 in bath mat leaves 6 in of the 30 in of floor in front.

A 24 × 40 in bath mat.

Worked example

Along a 72 in double vanity with 30 in of floor

What we know

• Vanity: 72 in wide, two sinks
• Floor in front: 30 in

How it works out

1. Along a 72 in double vanity, one runner across both sinks, no longer than the vanity.
2. A 24 × 72 in runner leaves 6 in of the 30 in of floor in front.

A 24 × 72 in runner.

Bath mat size chart

The calculator’s pick beside common tubs and outside each kind of shower, with 30 in of clear floor in front, enough for a comfortable bathroom.

Mats and runners for vanities

Single-sink vanities run 24 to 48 in wide and double-sink vanities 48 to 72 in.

Standard bath mat sizes

• 17 × 24 in: the smallest standard size, for a toilet, a pedestal sink or a small shower stall.
• 20 × 30 in: the most popular all-purpose size.
• 21 × 34 in: the standard size, and the size of a standard bath rug.
• 24 × 36 in and 24 × 40 in: for a larger tub, an open shower or a wider vanity.
• 30 × 50 in: for a freestanding tub or a full-size walk-in shower.
• Runners: 24 × 60 in, 24 × 72 in, 30 × 72 in and 30 × 84 in, for a double vanity.
• Contour rugs: about 20 × 24 in, cut to fit around the base of a toilet. A toilet rug is optional.

Backing and floors

• Non-slip: every bath mat or rug needs a non-slip backing, a non-slip pad or double-sided tape under it, so it won’t slip. Keep the bathroom floor itself slip-resistant, or cover it with slip-resistant materials that stay put.
• For older adults: skip throw rugs and small area rugs altogether, and put nonskid mats or strips on every surface that may get wet.
• Vinyl and LVT: rubber- or latex-backed mats can stain or discolor vinyl and LVT. Choose a colorfast, non-staining mat with a vinyl or polypropylene backing, or a woven rug.
• Doors: an interior door usually clears the floor by about 1/2 to 3/4 in, so choose a low-pile or flat mat where the door swings.
• Fit: a mat that’s too large and doesn’t lie flat around fixtures is a tripping hazard.

Washing and replacing

• Wash: about once a week in cold water, more often with several people in the house.
• Dry: tumble dry low or hang dry, and keep rubber backing out of the dryer.
• Replace: most bath mats last one to two years.

Then size the shower curtain and liner with the shower curtain size calculator, or the mirror over the vanity with the vanity mirror size calculator.