Tile Calculator

Each tile effectively occupies its own size plus the grout gap, so the tool divides your area by that footprint, then applies waste — defaulting to 10% for straight layouts and 15% when you select diagonal or herringbone, which produce more offcuts. A tiles-per-box field turns the count into boxes.

Common uses

• Buy tile for a bathroom floor with the right cushion for cuts
• See how a diagonal layout changes the order quantity
• Convert a tile count into whole boxes

Example

50 sq ft, 12×12 in tile, 1/4 in grout, straight layout

48 tiles exact → buy 53 → 6 boxes of 10

Limitations

• Waste percentages are rules of thumb; rooms with many corners need more
• Assumes a single tile size — mixed patterns need separate runs

How many 12x12 tiles do I need for 100 square feet?

With a 1/4 in grout gap, each tile occupies 12.25×12.25 in, so 100 sq ft takes 96 tiles exactly — buy 106 with the 10% waste default. Without accounting for the gap you'd wrongly plan an even 100.

How much extra tile should I buy for cuts and waste?

10% for straight or grid layouts and 15% for diagonal or herringbone, which produce more offcuts — this calculator switches the default automatically when you pick the layout. Rooms with many corners, alcoves, or plumbing penetrations can need even more.

Does the grout gap change how many tiles I need?

Yes, slightly — each tile effectively occupies its own size plus the gap on two sides, so wider joints mean fewer tiles per square foot. Going from a 1/8 in to a 3/8 in gap on 12×12 tile reduces the count by about 4%.

Why do tile suppliers say to keep leftover tiles?

Tile dye lots vary between production runs, so a replacement bought later may not match your floor. Keeping a few spares from the same boxes is the only reliable way to repair a cracked tile invisibly.

Does this tile calculator send my inputs anywhere?

No. The tile and box counts are calculated in your browser as you type — nothing is transmitted to a server or saved.