How Many Tiles Do I Need? Tiles per Square Foot and by Room Size
Part of the project planner: Planning new floors and tile.
A 12 × 10 ft floor of 12 × 12 inch tiles takes 130 tiles with 10% extra for cuts, which is 13 boxes of 10, with 2 bags of thinset and about 9 pounds of grout. The tiles are the area divided by the area of one tile with its joint, plus waste. The tile calculator works it out for your own room, tile, joint and waste, and the boxes.
Tiles per square foot
With 1/8 inch joints:
| Tile size | Tiles per sq ft | Tiles for 100 sq ft (with joints, no waste) |
|---|---|---|
| 4 × 4 in | 9.00 | 847 |
| 6 × 6 in | 4.00 | 384 |
| 12 × 12 in | 1.00 | 98 |
| 12 × 24 in | 0.50 | 50 |
| 18 × 18 in | 0.44 | 44 |
| 24 × 24 in | 0.25 | 25 |
Tiles for common rooms
With 10% waste, in whole tiles:
| Room | Area | 12 × 12 in | 12 × 24 in | 6 × 6 in |
|---|---|---|---|---|
| 5 × 8 ft | 40 sq ft | 44 | 22 | 169 |
| 8 × 10 ft | 80 sq ft | 87 | 44 | 338 |
| 10 × 12 ft | 120 sq ft | 130 | 65 | 507 |
| 12 × 15 ft | 180 sq ft | 194 | 98 | 761 |
| 15 × 20 ft | 300 sq ft | 324 | 163 | 1267 |
How much waste
For the 12 × 10 ft floor of 12 inch tiles:
| Waste | Layout | Tiles | Boxes of 10 |
|---|---|---|---|
| 10% | Straight layout | 130 | 13 |
| 15% | Diagonal layout or a lot of cuts | 136 | 14 |
| 20% | Small rooms with many cuts or a pattern | 142 | 15 |
Grout needed by joint width
For the 120 sq ft floor of 12 inch tiles (3/8 inch thick):
| Joint | Grout |
|---|---|
| 1/16 in | 4.7 lb |
| 1/8 in | 9.4 lb |
| 3/16 in | 14.1 lb |
| 1/4 in | 18.8 lb |
A wider joint takes more grout. See the tile, grout and thinset guide for the thinset and the notch size.
Tips for ordering tile
- Measure the area to tile, and take off any large areas that will not be tiled, such as a tub or a built-in vanity.
- Round up to full boxes, and add the extra for waste. Tile is sold by the box, so the leftovers are a spare for repairs.
- Buy all the tile at the same time, from the same lot: color and size vary between batches.
- Lay out the tiles dry before you start, to avoid thin cuts at the walls.
- Large-format tiles need a flat floor and a bigger notch of thinset.
For the whole job from the subfloor to the grout, see the tile project materials calculator and the materials list for a bathroom floor. Estimates only: confirm the quantities with your supplier.
Frequently asked questions
How do you calculate how many tiles you need?
Divide the area of the floor by the area of one tile (with the joint) and add 10% for cuts. A 12 × 10 ft floor (120 sq ft) with 12 inch tiles is 130 tiles including 10% waste.
How many 12x12 tiles per square foot?
One: a 12 × 12 inch tile covers a square foot. A 12 × 24 inch tile covers 2 sq ft, and a 6 × 6 inch tile is 4 to the square foot.
How much extra tile should I buy?
10% for a straight layout, 15% for a diagonal layout or a room with many cuts, and 20% for a pattern or a small room. Keep a few extra tiles for repairs: the dye lot may change.
How much thinset and grout do I need?
For 120 sq ft: about 2 bags of 50 lb thinset (with a 1/4 × 3/8 inch notch) and 9.4 pounds of grout for 1/8 inch joints.
Do I include the joint in the tile size?
Yes: the calculator adds the grout joint to each tile, so a wider joint needs slightly fewer tiles and more grout.
More guides
Tools & materials for this project
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Estimates only. Quantities depend on your materials, site and supplier. Confirm important numbers before you order, and follow local building codes for anything structural.