Flooring Calculator
Laminate, vinyl or hardwood boxes for the same room.
Floor & wall tile
How many tiles do I need?
Enter the floor or wall dimensions, pick your tile size, and the calculator returns the exact number of tiles and full boxes — with a professional waste percentage applied. A 10 × 10 ft room in 12 × 12 in tiles needs about 121 tiles + 10% = 133 tiles, which works out to roughly 14 boxes at 10 sq ft per box.
Tile is sold by the full box and most stores won't take a partial box back, so rounding up is part of the estimate. Count floors, walls and backsplash as separate areas, apply 10% waste for a straight grid layout and 15% for diagonal, herringbone or large-format tile, and the calculator returns the pieces and whole boxes you need — plus the total square footage, handy when a retailer prices per square foot.
Frequently asked questions
How many 12×12 tiles do I need for a 10×10 room?
A 10 × 10 ft room is 100 sq ft, and each 12 × 12 in tile covers 1 sq ft. With the standard 10% waste that is 110 tiles — usually sold as 11 boxes if a box covers 10 sq ft.
Should I order 10% or 15% extra tile?
10% covers a straightforward grid layout. Choose 15% for diagonal or herringbone patterns, 24-inch large-format tile, or rooms with many corners, doorways and niches where cutting waste is higher.
Does the grout line change how many tiles I need?
For standard 1/8 to 1/4 inch grout joints the effect is a fraction of a tile per row — the 10% waste allowance already absorbs it. Only ultra-wide 1/2 inch joints change the count noticeably.
How do I measure a backsplash for tile?
Measure the width of the countertop run and the height from countertop to the underside of the cabinets (typically 18 in). Multiply width × height for the area, then add 10–15% waste for outlets and edges.
How do I calculate tile for a bathroom wall or shower surround?
Measure each wall's width and the height you plan to tile (often to the ceiling or 6 ft in a shower), multiply for each wall and add them up, then deduct the tub or niche openings. Enter every wall as its own area here and use 10–15% waste.
What if my room isn't a perfect rectangle?
Split the floor into two or more rectangles and enter each as its own area — a 15% waste setting is the safer choice when cuts cluster around bays, alcoves and doorways, so you never run short mid-project.
Tile Calculator
Imperial
ft
ft
sq ft / box
Check the carton — boxes usually cover 8–12 sq ft.
Waste / extra allowance
Enter your room size to see the result.
–
tiles
Grout joint width is negligible for tile counts; box coverage drives the number of cartons.
How it works
How to use this tile calculator
1Measure the area
Multiply length × width of the floor, wall or backsplash. For the backsplash, measure the area between the countertop and the upper cabinets only.
- Add length × width for every extra surface you tile.
- Walls: measure the full rectangle, then subtract any cabinet or opening areas.
- Use inches for small projects — one wall of a shower, for example.
2Choose the tile format
Tile sizes are given in inches. The calculator converts them to square feet per tile, then divides the room area by that number.
- 12 × 24 and 24 × 24 in tiles are the modern standard for floors.
- Subway tile is usually 3 × 6 or 4 × 12 in.
- Large-format tile generates more cutting waste on small rooms.
3Apply the waste percentage
Tiles always need extra: cutting, breakage during install, and spares for future repairs. Buy 10% extra for straight layouts, and 15% for diagonal patterns, large tiles, or rooms with lots of corners and niches. Keep the leftover cartons so discontinued tile can be matched later.
The math
Tile quantity formula
Tiles needed = (room area × (1 + waste)) ÷ (tile width × tile height ÷ 144)
Boxes needed = (room area × (1 + waste)) ÷ square feet per box (rounded up)
Worked example — 10 × 10 ft floor = 100 sq ft; 12 × 12 in tiles (1 sq ft each); 10% waste:
100 × 1.1 = 110 sq ft → 110 tiles; at 10 sq ft per box → 11 boxes.
100 × 1.1 = 110 sq ft → 110 tiles; at 10 sq ft per box → 11 boxes.
Waste guide
How much extra tile should you buy?
| Installation | Extra tile | Why |
|---|---|---|
| Straight grid, standard tile | 10% | Cuts at walls and around obstacles |
| Diagonal / diamond pattern | 15% | Almost every edge tile is cut |
| Large format (24 in+) | 15% | Fewer but bigger cuts, more breakage |
| Hermringbone / vertical brick | 15% | Complex layout = more waste |
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