Tile Calculator

Practical intro

Use this tile calculator when planning floor tile, wall tile, backsplash tile, shower tile, or a small renovation surface. Tile estimates need more than square footage because tile size, grout spacing, layout direction, cuts, breakage, and pattern matching affect the final count.

When to use this calculator

• Estimating tile count for a bathroom floor, kitchen backsplash, laundry room, mudroom, or shower wall.
• Comparing tile sizes before choosing a layout.
• Planning waste for diagonal, brick, herringbone, border, or mosaic layouts.
• Building a material budget before adding mortar, grout, backer board, waterproofing, trim, or labor.

Input explanation

• Project area is the total tiled surface in square feet.
• Tile length and width are entered in inches so the calculator can estimate each tile's coverage.
• Grout spacing adjusts the coverage estimate slightly by accounting for the joint between tiles.
• Waste factor covers cuts, breakage, pattern layout, edge pieces, and spare tile.
• Price per tile should match the unit price you will actually pay, not a per-box or per-square-foot value unless you convert it.

Formula or estimation method

Step-by-step worked example

A 120 square foot floor using 12 in by 12 in tile with a 1/8 in grout joint has an adjusted tile coverage of about 1.02 square feet. Before waste, the project needs about 118 tiles. With 10% waste, order about 130 tiles. At $2.40 per tile, the tile-only estimate is about $312.

Common mistakes

• Using room area but forgetting shower niches, returns, backsplash ends, or tub skirts.
• Entering tile dimensions in feet instead of inches.
• Using too little waste for diagonal, herringbone, or heavily cut layouts.
• Forgetting bullnose, edge trim, waterproofing, underlayment, mortar, grout, spacers, and sealer.
• Mixing tile from different dye lots without checking color variation.

Planning notes and limitations

• For many simple tile projects, 10% waste is a reasonable starting point; complex layouts can need 15% or more.
• Large-format tile may require flatter substrates and different setting materials than smaller tile.
• Wet areas may need waterproofing systems, slope, backer board, and code-compliant assemblies.
• Keep spare tile from the same lot for future repairs.

Project-specific checklist

Before treating the result as a shopping list, compare it with the exact product you plan to buy, the room or site condition, and the way the work will actually be installed. Small differences in package size, substrate prep, layout direction, openings, waste allowance, delivery rules, and trade requirements can change the final order. Keep a written note of the assumptions you used so a contractor, supplier, or helper can spot mismatches before money is spent.

Before you buy or schedule work

Use the estimate as a starting point, then confirm the exact product label, packaging unit, delivery minimum, site condition, and any contractor or code requirement. Rounding up is usually cheaper than stopping a project because one box, roll, gallon, board, or fixture is missing.