Measure the door, and the floor in front of it if it is tight. You get the door mat that fits, the smallest the makers’ 80% rule allows, the floor it leaves round it, and how thick it can be.
Door mat size
A 24 × 36″ door matas wide as the door · the smallest the 80% rule allows: 18 × 30″ (the door’s 80%: 28¾″)
Quick answer: mat makers say a door mat should be at least 80% of the door’s width, and ideally a little wider. For a standard 36″ front door that is 29″ or more: a 24 × 36″ mat matches the door, and 18 × 30″ is the smallest that passes. A double door takes one mat 5 to 6 ft wide: 3 × 5 or 4 × 6 ft. Leave 3–6″ of floor round it.
How to use the door mat size calculator
- Measure the door’s width, the door itself, not the frame; for a double door, both doors together.
- Measure the floor in front of it if it is tight: a narrow stoop, a small landing, a hallway.
- Measure the gap under the door if it swings over the mat.
- Read the mat, the floor it leaves and how thick it can be.
The rules behind the numbers
80% of the door, or wider
Mats4U’s entryway guide: “Your rug should be at least 80% of your door’s width” — “For a standard commercial 36-inch door, you need a rug that’s at least 29 inches wide (36 x 0.80 = 28.8)” — and “at least as wide as your door, but ideally a little wider”. Customat Designs: “Your doormat should be at least 80% the width of your door.” The calculator picks the smallest size as wide as the door, or the smallest 80% one when the floor is tight.
Double doors
Mats4U: “If you have double doors or sidelights, treat the entire unit as one wide entrance and apply the same 80% rule.” Matace: a double door takes “a single mat between 5 and 6 feet wide”.
The floor round it and the door over it
Mats4U: “Aim for at least 3-6 inches of bare floor on all sides”, and measure the gap under the door: “This measurement is your maximum pile height”.
Door mat size by door width
| Door | 80% of it | Smallest mat | As wide as the door |
|---|---|---|---|
| 30″ | 24″ | 18 × 30″ | 18 × 30″ |
| 32″ | 25⅝″ | 18 × 30″ | 24 × 36″ |
| 36″ | 28¾″ | 18 × 30″ | 24 × 36″ |
| 42″ | 33⅝″ | 24 × 36″ | 36 × 48″ |
| 60″ double | 48″ | 36 × 48″ | 3 × 5 ft |
| 72″ double | 57⅝″ | 3 × 5 ft | 4 × 6 ft |
A mat’s first number is its depth out from the door, the second its width along it. The sizes are Mats4U’s 18 × 30″, 24 × 36″ and 36 × 48″, and 3 × 5 and 4 × 6 ft for Matace’s 5–6 ft.
Four worked examples
A 36″ front door, room to spare. A 24 × 36″ mat, as wide as the door; 18 × 30″ is the smallest the 80% rule allows.
The same door on a 40″-wide stoop. A 24 × 36″ mat would leave 2″ a side, so an 18 × 30″ one: 5″ a side.
A 72″ double front door. A 4 × 6 ft mat; 3 × 5 ft is the least.
An inswing door with a ½″ gap under it. Any mat it swings over must be thinner than ½″.
Common door mat mistakes
- A mat narrower than 80% of the door. Customat Designs: “Any smaller, and it looks like a coaster for your shoes.”
- Two small mats at a double door. The makers say one wide mat.
- A thick mat under an inswing door. The door catches on it: check the gap first.
- A mat that fills the stoop edge to edge. Leave 3–6″ of floor round it.
Sizing the door itself? The free door size finder gives the door for the opening. For the rooms inside, the rug size calculator sizes an entry rug the bath mat size guide the mats in the bathroom, and the free 2D planner lays out the entry.
The door’s sizeRead next
Door mat size questions
What is the standard door mat size?
18 × 30″ and 24 × 36″ are the common front door sizes (Mats4U), with 36 × 48″ for a wide door or sidelights. For a 36″ door, the 24 × 36″ one is as wide as the door.
What door mat size do I need?
At least 80% of your door’s width, ideally as wide as the door or a little wider, with 3–6″ of floor round it. A 32″ door: 25⅝″ or more, so 18 × 30″ passes and 24 × 36″ matches it.
What size welcome mat for a double door?
One mat 5 to 6 ft wide (Matace): 3 × 5 ft is the least for a 72″ pair (80% of it is 57⅝″), 4 × 6 ft matches it.
What is the front door mat size for a 36-inch door?
24 × 36″, as wide as the door; 18 × 30″ is the smallest that meets the 80% rule (28¾″).
How thick can a door mat be?
Thinner than the gap under the door, if the door swings over it: “This measurement is your maximum pile height” (Mats4U). Outside the door’s swing, any thickness.