Convert a room's length and width into square feet
Enter the two dimensions you measured — in feet, or feet and inches — and get the area instantly, along with square yards, square meters, and acres.
How to measure a room in feet
Run a tape measure along the longest wall, floor to floor, corner to corner, and record it as feet and inches — for example 14 ft 6 in. Do the same for the wall running the other direction. Those two numbers are your length and width.
Multiply them together and you get the floor area in square feet. A room measuring 12 ft by 10 ft covers 120 sq ft, whether it is being carpeted, tiled, or painted. For rooms that aren't rectangular, split the space into rectangles, calculate each one separately, and add the results.
Always measure at floor level, not at the baseboard or a doorway, since alcoves and closets can throw off a single measurement taken elsewhere in the room.
Roughly how much material a square footage needs
Once you have your total, here's what that number typically means for common projects. Add 10% to the material total for cuts and waste.
Ordering mulch, soil, or gravel instead? Those are sold by volume, not area — use the cubic feet calculator to turn your square footage into cubic yards and a bag count.
| Project | Typical unit | Rule of thumb |
|---|---|---|
| Carpet | Sold by the sq yard | Divide sq ft by 9 |
| Tile | Sold by the box (sq ft/box on label) | Boxes = sq ft ÷ box coverage |
| Hardwood flooring | Sold by the sq ft | Order 10% extra for waste |
| Paint (one coat) | 1 gallon ≈ 350 sq ft of wall | Use wall area, not floor area |
| Turf / sod | Sold by the sq ft or pallet | Pallets usually cover 450–500 sq ft |
Common questions
What's the difference between a foot and a square foot?
A foot is a length — the distance along one line. A square foot is an area — a square that measures one foot on each side. You get square feet by multiplying two lengths together, such as a room's length and width.
How do I convert inches into this calculator?
Use the two boxes for each dimension: whole feet in the first, and any leftover inches in the second. 14 ft 6 in goes in as 14 and 6.
How do I find square footage for an L-shaped room?
Split the room into two or more rectangles, run each one through the calculator separately, and add the totals together.
Is square footage the same as floor area?
For flooring purposes, yes — floor area is usually what's meant by a room's square footage. For paint, you'd instead calculate wall area, which uses wall height and perimeter rather than floor dimensions.