How much tile should I buy?
Measure each tiled surface, subtract uncovered spaces, add an allowance, and round to whole cartons.
Short answer
Measure the tiled areas, remove islands and openings, apply an allowance for cuts and breakage, and use the carton coverage to plan the box count.
For homeowners buying tile for floors, walls, showers, backsplashes, or other measured areas.
How to do it
Add tiled areas
Enter each floor, wall, or backsplash section that will use the same tile.
Subtract uncovered spaces
Add islands, openings, and other areas that will not receive tile as exclusions.
Set size and allowance
Enter tile length and width, then choose an allowance that matches the layout and material.
Use carton coverage
Enter the coverage printed on the carton to see whole boxes, while keeping the piece count available for layout planning.
Formula
Net project area multiplied by one plus the allowance gives target coverage. Divide by tile area or carton coverage and round up.
Illustrative example
Measure each floor, wall, or backsplash section, subtract uncovered islands, and use the carton coverage for the purchase count. A separate tile-size count remains useful for layout planning.
Common mistakes
- Reducing the area for grout gaps
- Using one rectangle for a multi-surface project
- Forgetting shade, caliber, and pattern details
Before you buy
Confirm carton coverage, shade, caliber, pattern, setting materials, and the lot. Keep a few spare tiles when future matching matters.
What this guide does not cover
The tool does not design layout, grout joints, transitions, substrate preparation, waterproofing, or pattern-specific waste.
Use the calculator
Tile Calculator is the primary tool for this guide. You can also browse the other interior calculators.