Floor Tile Calculator
Calculate tiles and boxes for a floor installation, from a small bathroom to an open-plan living area.
How this calculator works
The calculator first finds your room area (Length × Width, in square feet), then finds the area of a single tile by converting its length and width from inches to square feet: (tile length in × tile width in) ÷ 144 (144 square inches in a square foot).
A waste allowance is added to the room area to cover cuts, breakage, and pattern layout (diagonal or offset patterns need more). The number of tiles is the waste-adjusted area divided by the area of one tile, rounded up. Boxes needed is that same area divided by how many square feet one box covers, rounded up to a full box.
Example calculation
Project: a 12 ft × 10 ft bathroom floor, using 12″ × 12″ tiles sold in boxes covering 15 ft² each, with 10% waste.
- Room area = 12 × 10 = 120 ft²
- With 10% waste = 120 × 1.10 = 132 ft²
- One tile = (12 × 12) ÷ 144 = 1 ft²
- Tiles needed = 132 ÷ 1 = 132 tiles
- Boxes needed = 132 ÷ 15 ≈ 9 boxes
Buying & material guidance
Straight-lay patterns typically need only 7–10% waste; diagonal layouts, herringbone, or rooms with lots of corners and cutouts (like bathrooms with fixtures) should use 15% or more. Large-format tiles (anything over 15″) also tend to need more waste allowance since offcuts are harder to reuse.
Always buy tile from the same dye lot when possible — color can shift slightly between production runs. It’s also worth keeping a full spare box after the job for future repairs, since matching tile years later is often impossible.
This tool uses the same calculation engine as our full Tile Calculator, with guidance tailored to this project type.
Frequently asked questions
Do I need to tile under cabinets or appliances?+
Generally no for permanent, built-in cabinets — tiling stops at the cabinet line. But it's common practice to tile under ranges, refrigerators, and dishwashers in case they're replaced later, so include that area in your total.
How many tiles do I need for a 12x12 room?+
For a 12 ft × 10 ft room (120 ft²) using standard 12x12-inch tiles with a 10% waste allowance, you'd need about 132 tiles — roughly 9 boxes if each box covers 15 square feet.
How much extra tile should I buy for waste?+
A 10% waste allowance covers most straight-lay installations. Increase this to 15% or more for diagonal patterns, herringbone layouts, or rooms with many cuts around fixtures and corners.
Should I buy tile by the box or by the piece?+
Tile is almost always sold by the box, and most retailers require full-box purchases. This calculator rounds up to the nearest full box so you know exactly how many to order.