Tile Calculator
How many tiles and boxes, with grout linesRuns in your browser
Rough material cost
$261Tile only, priced per square foot of tile bought. Add thinset, grout and backer board. Rough 2026 US average for ceramic/porcelain.
Material estimates only. Round up, buy a little extra, and check with your supplier. Structural work (footings, framing, roofs) must follow local building codes; consult a licensed contractor where required.
How it works
Formulas
Tiles = area ÷ ((tile length + joint) × (tile width + joint) ÷ 144) × (1 + waste %)Sizes in inches, area in square feet.
Worked example
Input: 10 × 8 ft floor, 12 × 12 in tiles, 1/8 in joints, 10% waste.
- Each tile covers 12.125² ÷ 144 = 1.021 sq ft.
- 80 ÷ 1.021 = 78.4 tiles.
- With 10% waste: 86.2 → 87 tiles.
Result: 87 tiles (9 boxes of 10).
How to use
- 1Enter the area's length and width.
- 2Enter the tile size and grout joint width.
- 3Add 10% waste (15% for diagonal layouts).
- 4Enter tiles per box to get the number of boxes.
FAQ
Does the grout line change how many tiles I need?
Slightly: each tile plus its grout joint covers a bit more than the tile itself. With 12 in tiles and 1/8 in joints, each tile covers about 1.02 sq ft.
How much extra tile should I buy?
10% for straight layouts and 15% for diagonal or patterned ones. Buy all tile from the same batch (lot number) so the shade matches.
Can I use metric units?
Yes. Switch to Metric and enter meters and centimeters; results show cubic meters, square meters or tonnes alongside US units.