To calculate how many tiles you need, first measure the length and width of your room to get the total square footage. Then divide by the area of one tile. Add 10-15% extra for waste and cuts. Our free tile calculator does all of this automatically.
What waste margin should I add for tiles?▼
For most projects, add 10% for waste. For diagonal patterns or rooms with many corners, add 15%. For complex mosaic patterns, consider 20%. Our calculator includes a customizable waste margin.
Can this calculator be used for wall tiles?▼
Yes, our tile calculator works for both floor tiles and wall tiles. Simply enter the dimensions of your wall area instead of floor area.
Is this tile calculator free to use?▼
Yes, our tile calculator is 100% free. No registration, no ads, and no data storage. All calculations happen in your browser.
Why should I add a waste percentage?▼
Cutting tiles to fit corners, edges, and pipes inevitably results in discarded scraps and occasional breakage. Adding 10% extra ensures you won't run short.
How do I measure irregular rooms?▼
Break down complex or L-shaped rooms into smaller rectangular sections, calculate the area of each section separately, and add them together.
Plan a Tile Quantity
Enter the room dimensions and tile dimensions in matching units, then choose a waste percentage. The calculator finds surface area, tiles needed, and an allowance for cuts. Whole cartons must be rounded up after checking the package coverage. For a 12 by 10 foot room, the area is 120 square feet; with 10% waste, plan for 132 square feet before converting that requirement to boxes.
Assumptions and formula
Room area is length × width. Tile area is tile length × tile width. The basic tile count is room area divided by tile area, then rounded up; the actual layout may need more because a cut piece cannot always be reused. Diagonal, herringbone, staggered, and multi-size patterns often create more offcuts than a straight grid.
Buying and installation checks
Confirm the tile is rated for the intended wall or floor, check water absorption and slip resistance, and buy boxes from the same lot when color matters. Dry-lay several rows, inspect the narrow cuts at edges, and keep a spare box labeled with the lot number. Check the substrate, grout joint, adhesive, and manufacturer instructions before installation.
Mistakes and limitations
Do not confuse inches with feet, forget a wall height, treat waste as usable area, or assume every package has the same coverage. Openings, niches, cabinets, and thresholds may require separate measurements. The calculator is an estimate and cannot judge substrate condition or an installer’s layout. Read the tile buying guide and use the square footage calculator for a second area check.
A final order checklist
Confirm the measured area, tile coverage per box, waste percentage, grout width, pattern direction, and spare material before checkout. Inspect boxes for damage and shade variation before opening adhesive. Keep the layout centered where possible and avoid ending with unsafe narrow strips. The calculator supplies quantity arithmetic; a qualified installer should confirm substrate preparation, movement joints, waterproofing, and product compatibility.
Tile Quantity Formula
Calculate room area first, then divide by the coverage of one tile. A 12 by 24 inch tile covers 288 square inches, or 2 square feet. For a 120-square-foot room, 120 ÷ 2 = 60 tiles before waste. With 10% allowance, 60 × 1.10 = 66 tiles. Round up to a whole tile and then to complete boxes because an opened box may not be returnable.
Layout, grout, and ordering
Tile dimensions are nominal; verify the actual product coverage and recommended grout joint. Dry-lay a row to see where cuts fall, especially around doors, cabinets, drains, and corners. Straight layouts commonly use 10% waste, while diagonal and patterned layouts may need 15% or more. Buy the same dye lot, save the product details, and keep spare pieces for repairs.
Common Mistakes and FAQs
Do not multiply the room perimeter, mix inches with feet, or subtract uncertain openings. Should waste be added before division? No, calculate theoretical tiles first, then apply the allowance. What if two rooms use the same tile? Calculate each layout separately, add the results, and consider keeping extra from one lot. Use the area calculator for irregular rooms and read the tile buying guide before ordering.
Box and Layout Checklist
Check the tile’s stated coverage, box quantity, caliber, shade, and recommended joint. Measure the longest run and the smallest edge piece before committing to a centered layout. A narrow cut may be avoided by moving the reference line a few inches. Include threshold transitions and movement joints where the installation instructions require them.
After installation
Store spare tiles with the product name and lot information. Photograph hidden plumbing or underfloor details before covering them. Keep the final calculation and receipts with the maintenance records in case a future repair needs a matching batch.
Pattern Allowance
Large-format tile, offset patterns, niches, and diagonal cuts often create more offcuts than a simple grid. Measure the usable wall or floor after framing, allow for grout, and confirm that the substrate is ready. Order enough from one production lot for the complete visible area.
Keep the record
Save a box label, layout sketch, and final quantity. These details make future repairs faster when a product is discontinued.
Plan tile quantity with a realistic allowance
Start with the net surface area, then account for tile size, grout joints, cuts, and breakage. A rectangular floor uses length times width. If a room is 10 ft by 12 ft, the area is 120 square feet. With 10% waste, order enough for 132 square feet. The number of boxes must be rounded up because partial cartons are often unavailable or leave too little matching material.
Worked tile example
A 12 by 15 ft room contains 180 square feet. For 12 by 12 inch tiles, each tile covers 1 square foot before waste, so a simple estimate is 180 tiles. A 10% allowance raises this to 198 tiles. If a box contains 10 tiles, buy 20 boxes. For a wall, calculate each wall rectangle and subtract doors or windows that will not be tiled.
Steps that prevent shortages
Measure length and width at several points and use the largest practical dimension.
Convert all measurements to one unit before finding area.
Choose a waste rate: about 10% for a simple straight layout and more for diagonal or patterned work.
Check tile coverage per box, lot or dye number, and return policy before ordering.
Assumptions and FAQs
The calculator estimates quantity; it does not design a layout or account for subfloor leveling. Grout joints slightly change coverage, and a large-format tile may require a flatter surface. Should I include extra tile? Yes, especially for repairs because future batches may not match. Why does the store's box count differ? Packaging coverage and rounding explain most differences. Keep a diagram of cuts and reserve uncut tiles for visible areas. Use the square footage calculator first when the room has multiple sections.
The Complete Tile Quantity Guide: Formulas, Examples & Tips
Learn exactly how to calculate how many tiles you need for any room — including waste, patterns, and ordering strategies — so your project never runs short.
The Tile Quantity Formula Explained
The basic tile quantity calculation is a two-step process. First, calculate the room area. Second, divide by the coverage of one tile, then apply a waste allowance:
Room Area = Length × Width (in the same unit)
Base Tile Count = Room Area ÷ Tile Area
Total with Waste = Base Count × (1 + Waste% ÷ 100)
Always convert measurements to a consistent unit before calculating. If your room is in feet but your tile is in inches, convert the tile dimensions to feet first (divide inches by 12).
Step-by-Step Worked Examples
Example 1: Bathroom Floor (60×60 cm tiles)
Room: 3.2 m × 2.8 m | Tile: 60 cm × 60 cm (0.6 m × 0.6 m) | Waste: 10%
Room area = 3.2 × 2.8 = 8.96 m²
Tile area = 0.6 × 0.6 = 0.36 m²
Base count = 8.96 ÷ 0.36 = 24.9 → 25 tiles
With 10% waste: 25 × 1.10 = 27.5 → 28 tiles
If tiles come 6 per box: 28 ÷ 6 = 4.67 → 5 boxes
Example 2: Living Room Floor (12×12 inch tiles)
Room: 15 ft × 12 ft | Tile: 12 in × 12 in = 1 ft × 1 ft | Waste: 10%
Room area = 15 × 12 = 180 sq ft
Tile area = 1 × 1 = 1 sq ft
Base count = 180 ÷ 1 = 180 tiles
With 10% waste: 180 × 1.10 = 198 tiles
At 10 tiles per box: 198 ÷ 10 = 20 boxes
Example 3: Kitchen Backsplash (Diagonal Pattern)
Wall: 4 ft × 3 ft = 12 sq ft | Tile: 4×4 inch subway tiles | Diagonal pattern waste: 15%
Tile area in sq ft = (4/12) × (4/12) = 0.333 × 0.333 = 0.111 sq ft
Recommended Waste Percentages by Installation Type
The right waste allowance depends on the layout complexity, tile size, room shape, and installer experience:
Installation Type
Recommended Waste
Reason
Straight grid (regular room)
8–10%
Minimal cuts, predictable edges
Staggered / brick bond
10–12%
More edge cuts needed
Diagonal (45°) pattern
15–20%
Large corner triangles create waste
Herringbone pattern
15–20%
Complex angled cuts throughout
Large-format tiles (60cm+)
10–15%
Breakage risk; fewer but costly cuts
L-shaped or complex rooms
15%+
Multiple re-cut pieces required
Practical Buying & Installation Tips
Buy from one lot: Tiles from different production batches (dye lots) can have subtle color or size variations that are only visible when laid side by side. Always check the batch number on each box.
Dry lay first: Before applying adhesive, lay a row of tiles across the longest dimension to check cuts and centering. Adjust the starting line to avoid narrow slivers at the edges.
Keep spares: Store at least 3–5% of tiles after installation, labeled with the product code and lot number. Future repairs are nearly impossible if the tile is discontinued.
Verify tile dimensions: Nominal tile sizes (e.g., "60×60") may differ from actual calibrated dimensions. Check the technical datasheet for exact measurements before calculating.
Check the substrate: Large-format tiles require a flatter substrate (maximum 3mm deviation in 2 meters). Ensure the floor or wall is properly prepared to prevent cracking.
Frequently Asked Questions
How does a tile calculator estimate quantity?
It compares the project area with the coverage of each tile and then applies the selected waste allowance.
How much waste should I plan for?
The appropriate allowance depends on the layout, tile shape, cuts, pattern, and installer.
Can I use different tile sizes?
Yes. Recalculate using the exact tile dimensions for each area rather than mixing sizes in one calculation.
Why should I buy from the same batch?
Tiles from different production batches can sometimes vary slightly in shade or calibration.
