How do I calculate how much tile I need?

Measure the length and width of your space in feet, multiply them to get the square footage, then divide by the area of one tile to get the number of tiles. Add 10-20% extra for waste depending on your layout pattern. The formula is: Tiles Needed = (Room Area ÷ Tile Area) × (1 + Waste Factor).

How much extra tile should I buy for waste?

For a straight grid layout, add 5-10% extra. Brick or stagger patterns need 10-15%, diagonal layouts need 15-20%, and complex patterns like herringbone or chevron need 15-25% extra to account for angled cuts and pattern alignment.

How much tile do I need for a shower?

For a standard 3×3-foot shower with 8-foot ceilings, you need roughly 80-90 sq ft of wall tile (three walls × width × height) plus 9 sq ft for the floor. Add 15% for waste, giving you approximately 95-105 sq ft of tile total.

How many square feet does a box of tile cover?

Coverage varies by tile size and brand. A typical box of 12×12-inch tiles covers about 10-15 sq ft, while 6×6-inch tiles may cover 5-8 sq ft per box. Check the box label for exact coverage, and always divide your total square footage (including waste) by the box coverage to get the number of boxes needed.

Do I need different amounts of tile for walls vs. floors?

The calculation method is the same — measure length × height for walls and length × width for floors — but walls generally need slightly less waste allowance (5-10%) than floors (10-15%) because wall tiles are less likely to be walked on and broken during installation. However, walls with windows, outlets, or niches may require additional waste.

How much tile do I need for a backsplash?

Measure the width of your countertop area and the height from countertop to upper cabinets (typically 18 inches). Multiply width × height for each section, add them together, then add 10-15% for waste. A standard 10-foot kitchen backsplash typically needs 15-20 sq ft of tile.

Illustration: How Much Tile Do I Need? Complete Calculation Guide — Illustration for "How Much Tile Do I Need? Complete Calculation Guide"

How Much Tile Do I Need? Complete Guide to Calculating Tile Quantity

Whether you're tiling a bathroom floor, kitchen backsplash, shower enclosure, or entire room — this guide walks you through exactly how much tile to buy. You'll learn the universal formula, see waste factors for every layout pattern, and get quick-reference tables for common room sizes. Prefer to skip the math? Run the numbers in our free tile planner.

Quick Answer

Tiles Needed = (Room Area ÷ Tile Area) × (1 + Waste Factor) Measure your space in square feet, divide by the area of one tile, then add 10–20% for waste depending on your layout pattern. For example, a 10×12-foot room (120 sq ft) with 12×12-inch tiles needs 120 base tiles, or 132 tiles with 10% waste for a straight layout.

5–10%

straight / grid layout

10–15%

brick / stagger layout

15–25%

herringbone / complex

1What is the tile calculation formula?

Every tile quantity calculation uses the same core formula, regardless of whether you're tiling a floor, wall, or backsplash:

Area of Space (sq ft) ÷ Area of One Tile (sq ft) = Base Tiles

Base Tiles × (1 + Waste Factor) = Total Tiles Needed

For example, a 10×12-foot room (120 sq ft) using 12×12-inch tiles (1 sq ft each) needs 120 base tiles. With a 10% waste factor for a straight layout: 120 × 1.10 = 132 tiles.

Tip

Always convert tile dimensions to the same unit as your room measurements. A 12×24-inch tile = 1×2 feet = 2 sq ft per tile. A 6×6-inch tile = 0.5×0.5 feet = 0.25 sq ft per tile.

2How do you calculate tile for a floor?

Floors are the most common tiling surface. Here's how to measure and calculate:

Step 1: Measure the Room

Measure the length and width of the room in feet. For L-shaped or irregular rooms, break the space into rectangles, calculate each one separately, and add them together.

Step 2: Subtract Fixtures

Subtract permanent fixtures like vanity cabinets, islands, or built-in shelving. Don't subtract toilets or freestanding furniture — tile under them for flexibility.

Step 3: Add Waste Factor

Add 10% for straight layouts or 15–25% for complex patterns. This covers cuts at edges, breakage, and future repairs.

Example: A 10×12 bathroom = 120 sq ft. With a vanity (2×4 ft = 8 sq ft) subtracted: 112 sq ft. Using 12×24-inch tiles (2 sq ft each) with 10% waste: (112 ÷ 2) × 1.10 = 62 tiles.

3How do you calculate tile for walls?

Wall tile calculations use height instead of a second floor dimension. Measure each wall separately for the most accurate count:

Wall Area = Wall Width × Wall Height

Add together all the walls you plan to tile, then subtract windows, doors, and any areas you won't be covering.

Subtract Openings

A standard window is roughly 10–15 sq ft. A standard door opening is about 21 sq ft (3×7 ft). Subtract these from your total wall area before adding waste.

Waste for Walls

Walls with windows, electrical outlets, and niches typically need 10–15% waste. Simple accent walls with no cutouts may only need 5–10%.

Example: An accent wall measuring 12 ft wide × 9 ft tall = 108 sq ft. Using 4×12-inch subway tiles (0.33 sq ft each) with 10% waste: (108 ÷ 0.33) × 1.10 = 360 tiles.

4How do you calculate tile for a backsplash?

Backsplashes are smaller areas but often involve more cutouts around outlets, switches, and windows. The standard height from countertop to upper cabinets is about 18 inches (1.5 ft).

Backsplash Area = Counter Length × Backsplash Height

Don't Forget the Range Area

Behind the stove, the backsplash often extends up to the range hood — typically 30–36 inches high instead of 18. Calculate this section separately and add it to your total.

Waste Factor for Backsplashes

Add 10–15% waste. The smaller area means fewer tiles overall, but outlets and corners increase cutting waste proportionally.

Example: A 10-foot counter with an 18-inch backsplash = 15 sq ft. Range area adds 3 ft × 3 ft = 9 sq ft. Total: 24 sq ft. With 15% waste: 24 × 1.15 = 28 sq ft of tile needed.

5How do you calculate tile for a shower?

Showers require tile on multiple walls and the floor. Measure each surface separately:

Shower Walls

Measure each wall (width × height) individually. A standard 3×3-ft shower with 8-ft ceilings has three walls of 3×8 = 24 sq ft each, totaling 72 sq ft. If you tile to ceiling, the back wall and two side walls are all included.

Shower Floor

Shower floors are often 3×3 ft (9 sq ft) or 3×5 ft (15 sq ft). Small mosaic tiles are common for shower floors and may need 15% waste due to more grout lines and cuts around the drain.

Niches and Benches

Don't forget shower niches (typically 12×24 inches interior = ~4 sq ft with all sides) and corner benches (~6–8 sq ft of tile). These small areas still need their own calculations.

Example: 3×3-ft shower, 8-ft ceilings: 3 walls × (3 × 8) = 72 sq ft walls + 9 sq ft floor + 4 sq ft niche = 85 sq ft. With 15% waste: 85 × 1.15 = 98 sq ft of tile needed.

6What waste percentages apply by layout pattern?

The layout pattern you choose directly affects how much extra tile you need. Patterns with angled or staggered cuts produce more waste than simple grid layouts:

Layout Pattern	Waste %	Why
Straight / Grid	5–10%	Minimal cuts — only at room edges
Brick / Running Bond	10–15%	Staggered rows require half-cuts at each end
1/3 Offset Stagger	10–15%	Similar to brick but with 1/3 offsets
Diagonal / 45°	15–20%	Every edge tile is cut at an angle
Herringbone	15–25%	Many angled perimeter cuts and V-shaped ends
Chevron	15–25%	Pre-cut angles still waste material at borders
Versailles / Modular	20–25%	Multiple tile sizes; complex fit at edges

Pattern-Aware Calculations

Most online calculators only give you a flat percentage. Our tile calculator generates actual cut lists based on your chosen pattern — so you see exactly which tiles get cut and how much material is really wasted.

7How much tile do common room sizes need?

Use this table for a rough estimate of how many 12×12-inch tiles you need for common room sizes (including 10% waste for a straight layout):

Room Size	Square Feet	12×12" Tiles (with 10% waste)	Boxes (10 tiles/box)
5×5 ft	25 sq ft	28	3
6×8 ft	48 sq ft	53	6
8×10 ft	80 sq ft	88	9
10×10 ft	100 sq ft	110	11
10×12 ft	120 sq ft	132	14
12×12 ft	144 sq ft	159	16
12×16 ft	192 sq ft	212	22
15×20 ft	300 sq ft	330	33

Need a Different Tile Size?

This table uses 12×12-inch tiles. For other sizes, divide your room's square footage by the tile area in square feet. For example, with 6×6-inch tiles (0.25 sq ft each), a 100 sq ft room needs 400 base tiles + waste. Use our calculator for any tile size and pattern.

8Pro Tips

Always round up to full boxes. You can't buy individual tiles at most retailers, and having a few extras is better than being one tile short.
Buy all tile from the same lot. Dye lots vary between production runs. Ordering the exact same SKU later may not match.
Keep 2–3 spare tiles after installation. Store them for future repairs. Matching discontinued tile years later is nearly impossible.
Dry-lay before committing. Arrange tiles on the floor without adhesive to check pattern alignment and identify awkward cuts before you start.
Use our pattern-aware calculator. Unlike generic square-footage calculators, TilePro Calculator shows visual cut lists and exact tile counts for your specific pattern — herringbone, brick, stagger, and more.

Skip the Math — Calculate Instantly

Enter your room dimensions, choose your tile size and pattern, and get an exact tile count with visual layout preview. Our calculator handles cut lists and pattern alignment automatically, with a waste allowance you can adjust.

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Written by the TilePro Editorial Team

Tile-installation researchers and calculator engineers — every guide is grounded in real waste-per-pattern data from the calculator.

Last reviewed May 18, 2026