Guide
How much tile do I need?
Four steps: measure the surface, subtract openings, add a waste allowance for your layout pattern, and round up to full boxes. Here is each step the way an estimator does it — and the same math the TileCount app runs per space.
1. Measure the surface
Floors: width × length in feet. Walls, backsplashes, showers, and tub surrounds: width × height per wall, added together. Measure in feet and inches, then convert inches to decimals (6 inches = 0.5 ft).
2. Subtract openings
Doors, windows, and fixtures you will not tile behind come out of the total: subtract width × height for each. A tiled niche adds a little back — the back of the niche replaces the wall cutout, so only the short return sides add area.
3. Add pattern waste
Cutting waste depends on the layout. Typical planning allowances — the same defaults TileCount uses:
- Stacked — 8%
- Straight — 10%
- Running bond — 10%
- Diagonal — 15%
- Herringbone — 20%
- Chevron — 25%
Small rooms with many edges, out-of-square walls, and natural stone (dye-lot and breakage risk) can justify more.
4. Round up to full boxes
Tile sells by the box. Divide the waste-adjusted area by the coverage printed on the box and round up:
boxes = (net area × (1 + waste%)) ÷ sq ft per box, rounded up
Worked example
A 10 × 12 ft floor in a straight layout with 10 sq ft per box:
- Net area: 10 × 12 = 120 sq ft
- With 10% waste: 120 × 1.10 = 132 sq ft
- Boxes: 132 ÷ 10 = 13.2 → round up to 14 boxes (140 sq ft purchased)
Or skip the arithmetic: the free tile calculator runs this exact formula.
Beyond the tile itself
A real material list also needs thinset (coverage varies by trowel size and tile format), grout (joint width, tile size, and joint depth drive it — small tile uses far more grout per square foot), backer board or uncoupling membrane, waterproofing for wet areas, movement-joint sealant, and trim. The TileCount app estimates all of these per space and rolls them into a client-ready proposal; the in-app calculator and your first saved job are free.
Estimates are not guarantees. Always verify quantities, dimensions, box coverage, manufacturer instructions, local code requirements, and jobsite conditions before ordering materials, signing a contract, or starting work.