Start with area, not the carton
Pros start with the surface, not the box. Measure the floor or wall in feet, multiply for square footage, then decide how much overage the layout will burn. Only after that do they convert to tiles or boxes. The common DIY miss is ordering exact net area — every cut edge and every broken piece comes out of that order, and a mid-job reorder often lands in a different dye lot.
One canonical tool covers floor, shower, backsplash, and diagonal work. Switch the application mode above for the waste starting point, then jump to the matching section below for a worked example. Companion how-to guides for each application will link here as they ship — we are not splitting this into duplicate calculators that hide the same math behind different URLs.
Floor tile calculator
A rectangular floor is length × width in feet. Choose Floor so waste starts at 10% — the straight-layout convention in our materials data, not a manufacturer yield. Raise it for doglegs, many doorways, or large-format porcelain that punishes a bad cut.
Example state
10 ft × 10 ft floor · 12″ × 12″ tile · 10% waste → 100 sq ft net → 110 sq ft to order → 110 tiles
Jump to calculator and keep Floor selected to reproduce it.
Shower tile calculator
Showers are almost never one clean rectangle. Measure each wall plane (or a careful total), subtract large openings you will not tile, and use Wall / shower / splash so waste starts at 15%. Niches, benches, curbs, and valve cutouts are why shower waste runs higher than a simple floor — and why a single “standard bathroom” preset would lie.
Example state
One 5 ft × 8 ft shower wall · 12″ × 12″ tile · 15% waste → 40 sq ft net → 46.0 sq ft to order → 46 tiles
Add the other walls the same way, or enter a combined measured area. Busy surrounds often want more than 15%.
Tile backsplash calculator
A backsplash is a short wall: run length × height. Use the same wall/shower mode and waste starting point. Subway and mosaic face sizes change the piece count fast even when square footage barely moves — enter the actual tile, not a “standard subway” guess.
Example state
10 ft run × 1.5 ft high · 3″ × 6″ tile · 15% waste → 15.0 sq ft net → 17.3 sq ft to order → 138 tiles
Outlets, windows, and end returns eat extras. Attic stock for a future repair is separate from this cut-waste field.
Tile square footage calculator
Square footage is the first line of every honest takeoff: length (ft) × width (ft) = net sq ft. Waste turns that into order square footage. Tile count is order sq ft divided by one tile’s face area (inches × inches ÷ 144), rounded up. If you only need coverage to compare quotes, stop at order sq ft — the hero number above still shows tiles because that is what most people buy.
Example: the 10×10 floor above is 100 sq ft net and 110 sq ft to order at 10% waste, before you care whether the tile is 12×12 or 6×24.
How many boxes of tile
Carton coverage is SKU-specific. We do not invent “15 sq ft per box” as a site constant the way Quikrete publishes bag yields. Enter sq ft per box from your packaging; the tool divides order square footage by that figure and rounds up to whole boxes.
Example state (packaging figure, not a brand preset)
Same 10×10 floor · 10% waste · carton labeled 15 sq ft/box → 110 sq ft to order → 8 boxes
Diagonal and pattern layouts
Choose Diagonal / pattern so waste starts at 20%. Every perimeter piece takes an angle cut; triangular scraps rarely return to the field. Herringbone and other busy patterns belong in the same judgment bucket — edit the percent for large-format tile or a simple room.
Example state
10 ft × 10 ft · 12″ × 12″ · 20% diagonal waste → 120 sq ft to order → 120 tiles (10 more than the straight floor example)
Waste is a judgment call, not a published table
Unlike bagged concrete yields or manufacturer grout coverage charts, the trade does not publish a free public table that says “use X% for this pattern.” Field practice clusters around roughly 10% for a straight floor, 15% for showers and walls with fixtures, and 20% for diagonal or busy patterns — but your room wins over any default. The percentages here are labeled trade conventions you can edit, not TCNA Handbook cells. Full sourcing notes live on the methodology page.
Why this tool will not invent box coverage
Thousands of SKUs print different square feet per carton. Fabricating a handful of brand presets would be dishonest the way Quikrete bag yields are not — those three sizes really do share published numbers. Enter sq ft per box from your packaging if you want a box count; otherwise trust the tile count and order square footage.
Dye lots matter more than people expect. A second order of the “same” SKU can shift shade enough to show on a continuous floor. Attic stock for future repairs is a different decision from cut waste during install — both may land near 10%, but only cut waste belongs in this calculator’s waste field. Once the tiles are counted, joint fill belongs on the grout calculator.