Tile Calculator
Estimate how many tiles, bags of thinset mortar, and bags of grout you need for your flooring or wall project.
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Tile & Thinset Measurement
Enter the dimensions of your room and the dimensions of your individual tiles. Our calculator handles the math and adds a 10% waste factor for edge cuts and breaks.
How to Use the Tile Calculator
Tiling requires three main materials: the tile itself, the thinset mortar to stick it down, and the grout to fill the joints. Measuring accurately ensures everything matches and you don't run out of mortar halfway through.
- Measure the room: Measure the length and width of the floor or wall area you are tiling.
- Enter the tile size: Check the box for your tile dimensions. Common sizes are 12x12, 12x24, or 6x24 planks.
Tile Calculation Formula
We convert one tile to square feet, divide the project area by that coverage, and round up before applying the selected waste allowance.
Step 1: Convert Tile to Sq Ft
Tile Area (sq ft) = (Length in. × Width in.) ÷ 144
Step 2: Calculate Tile Count
Total Pieces = (Room Area ÷ Tile Area) × 1.10 (Waste)
Step 3: Calculate Mortar & Grout
Thinset Bags = Room Area ÷ 70 sq ft
Grout Bags = Room Area ÷ 100 sq ft
Tile Example Calculation
You are tiling an 8-foot by 10-foot bathroom floor with 12x24 inch large-format tiles.
- Room Area: 8 × 10 = 80 sq ft.
- Tile Area: (12 × 24) ÷ 144 = 2 sq ft per tile.
- Tiles Needed: (80 ÷ 2) × 1.10 = 44 tiles total.
- Thinset: 80 ÷ 70 = 1.14 (Buy 2 bags of thinset).
- Grout: 80 ÷ 100 = 0.8 (Buy 1 bag of grout).
- Related material: If you need other materials for this project, check out our Drywall Calculator.
Tips for Laying Tile
- Find the center: Dry-lay or mark reference lines before setting tile. The best starting point depends on focal lines, room shape, fixtures, and the size of edge cuts, so plan the layout before mixing mortar.
- Back-butter large tiles: If you are using tiles larger than 12x12, you should "back-butter" them. This means using the flat side of your trowel to scrape a thin layer of mortar directly onto the back of the tile before pressing it into the grooved mortar on the floor. It guarantees a 100% bond.
- Use leveling clips: If you are laying modern 12x24 or wood-look plank tiles, you must use a tile leveling system (clips and wedges). These tiles are prone to "lippage" where one corner sticks up higher than the next. The clips lock them perfectly flush.
Frequently Asked Questions
How much waste should I add for tile?
Ten percent is a common starting allowance for a simple rectangular layout. Diagonal patterns, complex cuts, breakage, matching lots, and spare tiles may require more; confirm the layout before ordering.
How much does a bag of thinset cover?
A standard 50 lb bag of thinset mortar will cover about 70 to 80 square feet of floor space when using a standard 1/4" x 1/4" square-notch trowel. If using large format tiles with a larger trowel, coverage will drop to 40-50 sq ft.
Sanded vs. Unsanded Grout: Which do I need?
If the grout lines between your tiles are 1/8 inch or wider, you must use sanded grout to prevent cracking. If the grout lines are smaller than 1/8 inch (like on glass backsplashes), use unsanded grout so it doesn't scratch the tile surface.
Do I need underlayment?
Yes, you should never tile directly over plywood. You must install a cement backer board (like HardieBacker) or an uncoupling membrane (like Schluter Ditra) over the wood subfloor first.