Tile Calculator
How many tiles and boxes do you need for that floor or wall?
How this is calculated
- Area = length × width
- Tile footprint = (tile width + grout) × (tile height + grout), converted from inches to feet
- Exact tiles = area ÷ footprint
- Tiles to buy = ⌈exact tiles × (1 + waste % ÷ 100)⌉ — always a whole box in practice, so check the box count below the tiles
Common questions
How many 12×12 tiles do I need for 100 square feet?
A 12 × 12 in tile covers exactly 1 sq ft, so 100 sq ft takes 100 tiles — 110 with a 10% cutting allowance. Keep the offcuts; straight cuts on square tiles are often reusable elsewhere in the room.
How much extra tile should I buy?
10% over the exact count for standard straight-lay patterns, 15% for larger tiles (more breakage per cut), and 15–20% for diagonal, herringbone, or intricate layouts. Also buy an extra box to keep as future repairs — dye lots change.
How do grout lines affect tile count?
Every tile effectively occupies slightly more than its face size — the grout line adds to each tile's footprint. With 1/8 in lines on 12 × 12 tiles across 100 sq ft, you need about 1% more tiles than the naive count. Small tiles with wide grout shift the number more.
How many tiles come in a box?
Varies by size: 12 × 12 floors often 8–10 per box (10–12 sq ft), 24 × 24 usually 5–6, subway tiles 50-100 per box. Divide the tile count by your box size and round up — the calculator gives total tiles; your supplier's box count does the rest.
Should I include the spaces under appliances or cabinets?
For floors, tile the full footprint before cabinets and appliances go in — replacing tile later under a loaded kitchen is far more expensive than the extra boxes now. For walls behind tall cabinets you can sometimes skip, but beware future layout changes.