Tile/Flooring Estimator
Estimate tiles needed with waste factor
Room area: 120 sq ft
132 tiles needed
~14 boxes (10/box) · includes 10% waste
Quick Facts
- •Add 10% waste for straight layouts
- •Add 15% waste for diagonal layouts
- •12×12" tile = 1 sq ft each
Estimating Tile Needs
Calculate the room area in square feet, then divide by the area of one tile. Always add 10-15% extra for cuts and waste — more for diagonal patterns. Common tile sizes are 12×12" (1 sq ft each), 18×18", and 24×24". Larger tiles mean fewer grout lines but more waste on cuts.
Understanding the tile/flooring estimator
Tile quantity is area divided by tile size, but the number you order is always larger than the number you install. Cuts at walls waste part of every edge tile, patterns like herringbone waste more, and you want spare boxes from the same production run because dye lots shift between batches.
Worked examples
Tiles for a 10 by 12 ft room using 12 by 24 in tiles
- 1Room area: 10 × 12 = 120 sq ft.
- 2Each tile: 12 × 24 in = 288 sq in, or 288 ÷ 144 = 2 sq ft.
- 3Tiles needed: 120 ÷ 2 = 60.
- 4Add 10 percent waste for a straight lay: 60 × 1.10 = 66 tiles.
66 tiles, which at 8 tiles per box is 9 boxes.
Adjusting for a diagonal layout
- 1Same 120 sq ft room, but tiles run at 45 degrees.
- 2Diagonal layouts need 15 to 20 percent waste rather than 10.
- 3120 × 1.18 = 141.6 sq ft of tile.
- 4141.6 ÷ 2 sq ft per tile = 71 tiles.
71 tiles for the diagonal layout, five more than a straight lay.
Waste factor by layout and room
| Situation | Waste to add |
|---|---|
| Straight lay, square room | 10% |
| Straight lay, many corners | 12 to 15% |
| Diagonal 45 degree | 15 to 20% |
| Herringbone or chevron | 20 to 25% |
| Large format over 24 in | 15% |
| Mosaic sheets | 10% |
Tiles per 100 square feet
| Tile size | Sq ft each | Tiles per 100 sq ft |
|---|---|---|
| 6 x 6 in | 0.25 | 400 |
| 12 x 12 in | 1.00 | 100 |
| 12 x 24 in | 2.00 | 50 |
| 18 x 18 in | 2.25 | 45 |
| 24 x 24 in | 4.00 | 25 |
| 6 x 36 in plank | 1.50 | 67 |
Add the waste factor on top of these figures.
Adhesive and grout coverage
| Material | Coverage | Notes |
|---|---|---|
| Thinset, 1/4 in notch | 80 to 95 sq ft per 50 lb bag | Standard floor tile |
| Thinset, 1/2 in notch | 40 to 50 sq ft per 50 lb bag | Large format |
| Sanded grout | 80 to 100 sq ft per 25 lb | Joints over 1/8 in |
| Unsanded grout | 100 to 120 sq ft per 25 lb | Joints under 1/8 in |
Frequently asked questions
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This calculator is for educational and reference purposes only. Always verify critical calculations independently.