Tile Calculator
Instantly estimate how many tiles, boxes, and how much waste allowance you need for floors, walls, bathrooms, showers, and backsplashes. Free, accurate, and works in both imperial and metric units.
Plan your tile project in 3 easy steps
Enter the area, choose your tile, and get an instant quantity with waste included.
What are you tiling?
This helps us label your estimate.
Pick a shape & enter the floor dimensions
Choose the outline that best matches your area, then fill in the measurements.
Enter the length and width of the area.
Choose your tile size
Dimensions are usually printed on the tile box.
Measure your space
Select the units used on your tape measure.
Area dimensions
Measure the longest length and width. We calculate each area as a rectangle.
Choose your tile
Pick a common size or enter the package dimensions.
How to Use the Tile Calculator
The calculator is designed to be straightforward for first-time DIYers while supporting complex projects with multiple surfaces and openings. Follow these steps:
- Choose your unit system — Imperial (feet/inches) for US projects or Metric (meters/centimeters).
- Enter your area— length and width of each surface, or switch to “I know the total area” if you already have the square footage.
- Subtract openings— deduct doors, windows, cabinets, or any area that won’t be tiled.
- Select your tile size — pick a preset (12×12, 12×24, etc.) or enter custom dimensions.
- Choose a grout gap — grout spacing slightly changes how much area each tile covers.
- Select your layout pattern — diagonal and herringbone patterns need more cuts, and more waste.
- Enter box info (optional) — tiles per box or square footage per box, so we can work out how many boxes to buy.
- Add pricing (optional) — get an estimated material cost.
How Many Tiles Do I Need?
The number of tiles you need depends on four things: your total area, the size of each tile, your chosen grout gap, and your waste allowance. The formula is straightforward:
Tiles with waste = Base tiles × (1 + Waste% ÷ 100)
Final count = Rounded up to the nearest whole tile
For example, a 10 ft × 12 ft bathroom floor (120 sq ft) tiled with 12×12 inch tiles (1 sq ft each) needs 120 base tiles. Adding 10% waste gives 132 tiles — always rounded up, never down.
How Tile Quantity Is Calculated
Every tile calculator result begins with converting your dimensions into a common unit — square feet (or square meters for metric). Here’s the full sequence:
- Project area: Multiply length × width for each surface and sum them together.
- Subtract openings: Deduct any doors, windows, or cabinets from the total.
- Effective tile area: One tile’s coverage including grout = (tile length + grout gap) × (tile width + grout gap).
- Base tile count: Net area ÷ effective tile area, rounded up.
- Add waste: Extra tiles for cuts, breakage, and future repairs.
- Box calculation: Divide total tiles by tiles per box, rounded up to full boxes.
We always use Math.ceil() (ceiling rounding) to ensure you never end up one tile short. See our How It Works page for the complete formula documentation.
How Much Extra Tile Should You Buy?
Tile waste accounts for cuts at edges, breakage during installation, and keeping spares for future repairs. The right waste percentage depends on your project:
| Layout Pattern | Recommended Waste | Why More? |
|---|---|---|
| Straight / Grid | 10% | Simple cuts along two edges only |
| Running Bond / Brick | 10% | Offset cuts are predictable and minimal |
| Diagonal (45°) | 15% | More cuts at all four walls; corner tiles are triangular |
| Herringbone | 15% | Complex angled cuts increase breakage risk |
| Chevron | 15% | Precision cuts required at each joint |
Your installer may recommend a higher waste percentage for intricate rooms, natural stone tiles that vary in size, or complex custom layouts. When in doubt, round up — leftover tiles are valuable for future repairs. Full guide: How Much Extra Tile Should You Buy?
Common Tile Sizes and Coverage
Tile sizes vary widely. Larger-format tiles can make small spaces feel bigger and mean fewer grout lines, but require a flatter substrate.
| Tile Size | Sq Ft Per Tile | Tiles Per 100 Sq Ft | Common Use |
|---|---|---|---|
| 3 × 6 in | 0.125 | 800 | Subway tile, backsplash |
| 4 × 4 in | 0.111 | 900 | Classic wall tile, bathrooms |
| 6 × 6 in | 0.25 | 400 | Bathrooms, small floors |
| 12 × 12 in | 1.00 | 100 | Most popular floor tile |
| 12 × 24 in | 2.00 | 50 | Modern large-format floors |
| 18 × 18 in | 2.25 | ~45 | Entryways, kitchens |
| 24 × 24 in | 4.00 | 25 | Large rooms, open-plan floors |
| 24 × 48 in | 8.00 | 12.5 | Large-format modern floors |
How to Calculate Floor Tiles
To calculate floor tiles, measure the length and width of the room in feet and multiply to get square footage. Most rooms aren’t perfect rectangles — for L-shaped rooms, split them into rectangles, calculate each separately, and add the totals.
Area: 12 × 10 = 120 sq ft
Each tile: 12 × 12 in = 1 sq ft
Base tiles: 120 ÷ 1 = 120 tiles
+10% waste: 120 × 0.10 = 12 → 132 tiles total
If box contains 10 tiles: 132 ÷ 10 = 13.2 → 14 boxes
For non-rectangular floors, our tile calculator lets you add multiple areas and calculate them together automatically. Full guide: How to Calculate Tiles for a Floor.
How to Calculate Wall Tiles
Wall tile calculation is identical in principle but requires measuring wall height × width for each wall. Don’t forget to subtract window and door openings — our calculator has a built-in opening deduction feature.
Wall: 8 ft × 9 ft = 72 sq ft
Window: 3 ft × 4 ft = 12 sq ft
Net wall area: 72 − 12 = 60 sq ft
Tile: 3×6 in subway tile = 0.125 sq ft each
Base tiles: 60 ÷ 0.125 = 480 tiles
+10% waste: 528 tiles
Tiling a shower surround or a kitchen backsplash? Those are wall projects too — see how to calculate shower tile and how to calculate backsplash tile.
How to Calculate Bathroom and Shower Tiles
Bathroom tile projects often combine multiple surfaces — floor, walls, and a separate shower enclosure. Calculate each separately and add them together, or use our “Add Another Area” feature to handle it in one pass.
For a shower, measure the three or four walls (back wall, two side walls, and optionally the ceiling). Use the opening subtraction for the shower door opening. Shower pans and niches may need separate calculations if the tile size differs.
Always add at least 10–15% waste for bathrooms — more if the tiles are small (mosaic) or the layout is complex. Full guide: How to Calculate Shower Tile, with a complete walk-in shower worked example and niche math.
Tile Calculation Example
Here’s a complete worked example for a bathroom renovation with floor, walls, and a window opening:
Floor: 8 × 5 = 40 sq ft
Back wall: 8 × 8 = 64 sq ft
Side walls: 2 × (5 × 8) = 80 sq ft
Window (deduct): 3 × 4 = −12 sq ft
Net total: 40 + 64 + 80 − 12 = 172 sq ft
Tile: 12×12 in (1 sq ft each), straight layout, 10% waste
Base tiles: 172 → Waste tiles: 18 → Total: 190 tiles
Boxes of 15: 190 ÷ 15 = 12.67 → 13 boxes
Run the same calculation instantly using our tile calculator above.
Frequently Asked Questions
- How do I calculate how many tiles I need?
- Measure your area in feet, multiply length × width for total square footage, then divide by the area of one tile. Add 10–15% for waste and round up. Use our tile calculator above for an instant, accurate result.
- How much extra tile should I buy?
- Add 10% for straight/grid layouts and 15% for diagonal, herringbone, or chevron patterns. Always buy whole boxes — leftover tiles serve as future repair stock.
- Does grout spacing affect how many tiles I need?
- Grout joints make each tile’s effective coverage slightly larger. A 1/8″ grout gap on a 12×12 tile gives about 1.02 sq ft coverage instead of exactly 1 sq ft. The difference is small but the calculator accounts for it precisely.
- How many 12×12 tiles do I need for 100 square feet?
- A 12×12 tile covers exactly 1 sq ft. You need 100 base tiles + 10% waste = 110 tiles for 100 sq ft (straight layout). Our tile calculator shows this instantly with box counts.
- How do I calculate tiles for an L-shaped room?
- Split the L-shape into two rectangles. Calculate each rectangle separately (length × width), add the areas, then proceed with the tile calculation as normal. Use the “Add Another Area” button in the calculator.
- Can I use this calculator for metric measurements?
- Yes. Switch to Metric mode to enter room dimensions in meters and tile sizes in centimeters. Results are displayed in square meters. The calculator supports both unit systems simultaneously.
Tile Calculation Guides
Need more detail? Our guides walk through tile measurement and estimation for specific room types and tile sizes.
Tile Calculation
How Many Tiles Do I Need?
The complete method for calculating tile quantity for any room, with worked examples for floors, walls, and bathrooms.
Floor Tiles
How to Calculate Tiles for a Floor
How to measure a floor, handle L-shaped rooms, account for waste, and work out exactly how many floor tiles and boxes you need.
Bathroom Tiles
How to Calculate Shower Tile
Measure a shower wall by wall and estimate tile for walls, floor, and niche — with a complete walk-in shower example.
Backsplash
How to Calculate Backsplash Tile
Measure a kitchen or bathroom backsplash and get an accurate tile count, including sheet-mounted mosaics and subway tile.