Measure the room wall to wall and get its floor area in square feet and square meters, for a rectangle or an L-shaped room. You also get the flooring to order and the wall area for paint.
Floor area
168 sq ft15.6 m² · 14′ × 12′
Quick answer: multiply the room’s length by its width, both in feet. A 12′ × 14′ room is 168 square feet (15.6 m²); a 12′ × 12′ room is 144 sq ft. For an L-shaped room, work out the whole rectangle and take off the corner that is missing. Order about 10% more flooring than the floor’s area.
How to use the square footage calculator
- Pick the shape. Rectangle for most rooms; L-shaped for a room with one corner cut out.
- Measure wall to wall at floor level and type the numbers in feet (12, 12.5 or 12′6″ all work) or switch to meters.
- Read the area in square feet and square meters, the flooring to order and the wall area for paint. Copy link keeps the result.
How to calculate the square footage of a room
- Rectangle: length × width. 12′ × 14′ = 168 sq ft.
- Feet and inches: turn the inches into a decimal of a foot first (divide by 12). 6″ = 0.5′, 3″ = 0.25′, 9″ = 0.75′. So 11′ 6″ × 13′ 3″ is 11.5 × 13.25 = 152.4 sq ft.
- L-shaped room: measure the two longest walls and multiply them, as if the room were a full rectangle. Then measure the two walls that meet at the L’s inside corner: they are the sides of the missing corner. Take that corner’s area off.
- Square meters: 1 m² = 10.76 sq ft, so divide square feet by 10.76 (or multiply square meters by 10.76 to go back).
- Walls: the perimeter × the ceiling height. An L has the same perimeter as the rectangle round it, so the same sum works.
Square footage of common room sizes
| Room | Square feet | Square meters | Flooring to order (+10%) |
|---|---|---|---|
| 10′ × 10′ | 100 sq ft | 9.3 m² | 110 sq ft |
| 10′ × 12′ | 120 sq ft | 11.1 m² | 132 sq ft |
| 11′ × 12′ | 132 sq ft | 12.3 m² | 146 sq ft |
| 12′ × 12′ | 144 sq ft | 13.4 m² | 159 sq ft |
| 12′ × 14′ | 168 sq ft | 15.6 m² | 185 sq ft |
| 12′ × 16′ | 192 sq ft | 17.8 m² | 212 sq ft |
| 14′ × 16′ | 224 sq ft | 20.8 m² | 247 sq ft |
| 15′ × 20′ | 300 sq ft | 27.9 m² | 330 sq ft |
| 16′ × 20′ | 320 sq ft | 29.7 m² | 352 sq ft |
| 20′ × 20′ | 400 sq ft | 37.2 m² | 440 sq ft |
Three worked examples
A 12′ × 14′ bedroom. 12 × 14 = 168 sq ft (15.6 m²). New flooring: order 185 sq ft. With an 8′ ceiling the walls come to 416 sq ft before the door and windows.
An L-shaped living room. The two longest walls are 20′ and 16′: 320 sq ft as a rectangle. The walls at the inside corner are 8′ and 6′, so the missing corner is 48 sq ft. The floor is 272 sq ft (25.3 m²).
A room measured in feet and inches, 11′ 6″ × 13′ 3″. 11.5 × 13.25 = 152.4 sq ft. Typing 11.6 for 11′ 6″ is the usual slip: it adds 1.3 sq ft that is not there. The calculator reads 11′6″ as typed.
Common mistakes
- Reading inches as tenths. 12′ 6″ is 12.5 feet, not 12.6.
- Measuring over furniture or the baseboard. Measure at the floor, wall to wall, where the flooring will actually go.
- Forgetting the closet. If the new floor runs into it, measure it as its own rectangle and add it.
- Buying exactly the floor’s area. Every row ends in a cut. Order 10% more, 15% for a diagonal or herringbone pattern.
Then use the number: the paint calculator turns the walls into gallons, the wallpaper calculator into rolls, and the rug size calculator picks the rug for the floor.
Draw the room to scale, L-shapes included, and try furniture in it: the free 2D room planner shows the square footage as you draw.
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Square footage questions
How do you calculate the square footage of a room?
Measure the length and the width in feet, wall to wall, and multiply them. A 12′ × 14′ room is 168 square feet. If a measurement has inches, divide them by 12 first: 12′ 6″ is 12.5 feet.
How many square feet is a 12×12 room?
144 square feet (13.4 m²). With 10% extra for cuts, order about 159 sq ft of flooring.
How do you calculate the square footage of an L-shaped room?
Multiply the two longest walls as if the room were a full rectangle, then take off the missing corner: the two walls that meet at the L’s inside corner, multiplied. A 20′ × 16′ L missing an 8′ × 6′ corner is 320 − 48 = 272 sq ft.
How do you convert square meters to square feet?
Multiply by 10.76: 10 m² is 107.6 sq ft and 20 m² is 215.3 sq ft. From square feet to square meters, divide by 10.76: 100 sq ft is 9.3 m².
How much extra flooring should I buy?
About 10% more than the floor’s area for cuts and waste, and 15% if it is laid diagonally or in a herringbone pattern, where every row ends in an angled cut.
How do you work out the square footage of the walls?
Add up the room’s walls (the perimeter) and multiply by the ceiling height. A 12′ × 14′ room with an 8′ ceiling has 52′ × 8′ = 416 sq ft of wall. For paint, take off about 20 sq ft for each door and 15 for each window.
How many square feet is a 10×12 room?
120 square feet (11.1 m²), and about 132 sq ft of flooring to order.