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Use our Square Footage Calculator →Tiling Tools & Supplies
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How to Calculate Tiles Needed
Getting the right number of tiles prevents extra trips to the store and ensures you have matching tiles from the same dye lot.
The Basic Formula
Step by Step
- Calculate area: Length × Width in square feet
- Calculate tile coverage: Tile length × width in square feet
- Divide: Area ÷ Tile coverage = exact tiles needed
- Add waste: Multiply by waste factor and round up
Why Add Waste?
Tiles break, cuts don't always go right, and you'll want extras for future repairs. Standard practice is 10% for regular layouts, 15% for diagonal patterns.
Common Tile Sizes
Floor Tiles
- 12" × 12" – Classic, works in any room
- 18" × 18" – Modern, fewer grout lines
- 24" × 24" – Large format, makes rooms look bigger
- 6" × 24" or 8" × 48" – Wood-look plank tiles
Wall Tiles
- 3" × 6" – Subway tile, timeless
- 4" × 12" – Large subway format
- Mosaic sheets – Backsplash and accents — try our Backsplash Calculator
- Shower tile – Walls, niches, and floors — try our Shower Tile Calculator
Frequently Asked Questions
How many tiles in a box?
It varies by manufacturer. Check the box label for sq ft per box, then divide your total area by that number.
Do I count the grout lines?
For most projects, the grout gap is small enough that you don't need to account for it. Our calculator includes a gap option for precision.
What if my room isn't a rectangle?
Break the room into rectangles, calculate each separately, and add them together. Then add your waste factor.
Should I buy extra tiles?
Always. Keep 2-3 extra tiles stored away for future repairs. Tile colors can vary between production runs.