Estimate a tile purchase from project area, individual tile dimensions, and the number of pieces in a box. This is an area-based shopping estimate with an adjustable waste allowance. It does not draw a cutting layout, size grout joints, or verify whether a tile and setting system are suitable for the surface.
Measure the surface in sections
Measure the length and width of a rectangular floor or wall in feet and multiply them to obtain square feet. For an irregular room, sketch smaller rectangles and total their areas. Keep wall and floor projects separate if they use different tiles. Areas hidden under cabinets should be included only if you actually intend to tile them.
Check the widest dimensions rather than assuming every wall is square. Doorways, alcoves, offsets, and out-of-square boundaries create cuts that may not be obvious from total area. Area alone cannot tell you whether an offcut from one edge will fit another. If layout is important, dry-plan the pattern before choosing the final allowance.
Use actual product dimensions and box counts
Enter tile length and width in inches. Tile face area is length × width ÷ 144, giving square feet per tile. Project area, increased by the selected waste percentage, is divided by tile face area and rounded upward to a whole-piece estimate. That piece count is divided by pieces per box and rounded upward again to whole boxes.
This calculation omits grout spacing. The joint width can affect exact layout, but it is not used to reduce the tile purchase estimate here. Mosaic sheets, irregular tiles, mixed-size patterns, and products sold by manufacturer-rated sheet coverage may not match an individual rectangular-tile model. Use the box’s rated coverage or a project-specific estimate in those cases.
Worked example: a rectangular floor
A floor measures 10 feet by 8 feet, totaling 80 square feet. A 12-by-12-inch tile covers 1 square foot. With a 10% allowance, the estimate covers 88 square feet and requires 88 tiles. If there are 10 pieces per box, the purchase estimate rounds up to 9 boxes, containing 90 tiles.
Those boxes provide 10 square feet beyond the original floor area, but the extra quantity will be used partly for cuts and possible breakage. It is not a promise of ten intact spare tiles after installation. If the layout is diagonal, the room has many edges, or you want retained repair stock, review the allowance before buying.
What else belongs in the shopping plan
Grout, mortar, underlayment, waterproofing, trims, movement joints, and tools are separate decisions with separate coverage requirements. This tool does not calculate any of them. Product instructions and the installation system should determine those choices, especially in wet locations. A correct tile count cannot compensate for an unsuitable substrate or unsupported installation method.
Check the supplier’s batch, shade, and caliber information and return policy when ordering. Whole-box rounding may already provide a little spare stock, but future repairs can be difficult to match if the product changes. Record the product name and batch information with your project notes. Use the purchase estimate as a starting point for a layout and supplier check rather than a substitute for either.
Common questions
Does the waste percentage include grout?
No. It increases the tile quantity to allow for cuts, breakage, and your chosen buffer. Grout quantity depends on separate joint and tile dimensions.
Can I enter a nominal tile size?
Use the most accurate dimensions available. Nominal marketing sizes can differ from the physical tile, and that difference matters more across larger areas.