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Tile Calculator

By Taro Schenker | Updated February 11, 2026

Quick Answer: To calculate tiles, divide the total area (sq ft) by the area per tile including grout joint: (tile length + grout) x (tile width + grout) / 144. For 12" x 12" tiles with 1/8" grout, each tile covers about 1.02 sq ft, so you need roughly 1 tile per sq ft. Add pattern waste: 0% for grid, 2% for running bond, 5% for diagonal or herringbone. Plan 4.5 lbs of thinset per sq ft and 4 lbs of tile weight per sq ft. Default waste factor is 10%. A 200 sq ft room with 12" tiles needs about 216 tiles.

Calculate how many tiles you need for your floor, wall, or backsplash project. Enter your dimensions, choose a tile size and pattern, and get the exact tile count, thinset requirements, and estimated cost.

How to Calculate Tile

The formula for calculating the number of tiles needed is:

Tiles = Area (sq ft) / ((Tile Length + Grout) x (Tile Width + Grout) / 144) x (1 + Waste%)
  1. Measure the length and width of your area in feet.
  2. Multiply length by width to get the total square footage.
  3. Calculate the area of one tile (including grout joint) in square inches, then divide by 144 to convert to square feet.
  4. Divide the total area by the area per tile to get the base tile count.
  5. Add your waste factor (10-15% depending on pattern and layout complexity).
  6. Round up to the nearest whole tile.

Tile Size Coverage

Quick reference for how many tiles you need at common sizes (assumes 1/8" grout joint):

Tile SizeTiles per sq ftTiles per 100 sq ft
4" x 4"8.5850
6" x 6"3.8380
12" x 12"1.0100
12" x 24"0.550
18" x 18"0.444
24" x 24"0.225

Tile Pattern Guide

  • Standard Grid: Tiles are laid in straight rows and columns. The most efficient pattern with minimal waste (0% extra). Best for beginners and clean, modern looks.
  • Diagonal (45-degree): Tiles are rotated 45 degrees to create a diamond pattern. Adds visual interest and makes small rooms look larger, but generates about 5% more waste from angled edge cuts.
  • Running Bond (Brick): Each row is offset by half the tile length, similar to a brick wall. A classic look that hides imperfections in walls and floors. Adds about 2% extra waste.
  • Herringbone: Tiles are laid in a zigzag V pattern at 45-degree angles. Creates a dramatic, high-end look but requires the most cuts and adds about 5% waste. Works best with rectangular tiles.

Formula Summary

Tile Count Formula: Calculate the number of tiles by dividing the total area by the effective area per tile (including grout joint), then applying waste and pattern bonus factors.

$$\text{Tiles} = \lceil A_{\text{sq ft}} \times \frac{144}{(L_t + G)(W_t + G)} \times (1 + W\% + P\%) \rceil$$

where $L_t$ = tile length (in), $W_t$ = tile width (in), $G$ = grout joint width (in), $W\%$ = waste factor, $P\%$ = pattern waste bonus.

Thinset Formula: $$\text{Thinset (lbs)} = A_{\text{adjusted}} \times 4.5$$

Weight Formula: $$\text{Weight (lbs)} = A_{\text{adjusted}} \times 4$$

PatternWaste Bonus
Standard Grid0%
Running Bond2%
Diagonal (45-degree)5%
Herringbone5%

Standard Assumptions: Waste factor of 10% accounts for cuts, breakage, and future repairs. Thinset coverage is 4.5 lbs per sq ft (1/4" x 1/4" square-notch trowel). Tile weight is estimated at 4 lbs per sq ft. A 50 lb bag of thinset covers approximately 60-75 sq ft.

Related Calculators

Estimates are for planning purposes only. Consult a qualified contractor for critical projects. Actual material requirements may vary based on site conditions, waste, and installation methods.

Pricing last verified: February 2026. Material prices vary by region, season, and supplier. Prices shown are national averages for planning purposes.

Frequently Asked Questions

How many tiles do I need per square foot?
It depends on the tile size. For 12" x 12" tiles, you need roughly 1 tile per square foot. For 6" x 6" tiles, you need about 4 tiles per square foot. For 4" x 4" tiles, you need about 9 tiles per square foot. Our calculator accounts for grout joint spacing, which slightly reduces the number of tiles needed.
How wide should grout joints be?
Standard grout joints are 1/8 inch (3 mm) for rectified tiles and 3/16 inch (5 mm) for non-rectified tiles. Larger format tiles (18"+ ) often use 1/16 inch joints. Mosaic tiles typically use 1/8 inch joints. Always check the tile manufacturer's recommendations for minimum grout joint width.
How much extra tile should I buy for waste?
Plan for 10% extra with a standard grid layout. Diagonal (45-degree) patterns and herringbone patterns generate more cuts and waste, so add 15% extra. For rooms with many obstacles (pipes, cabinets, odd angles), consider 15-20% extra. Always keep a few spare tiles for future repairs.
How much thinset mortar do I need?
Thinset coverage depends on trowel notch size and tile dimensions. As a general rule, plan for about 4-5 lbs of thinset per square foot when using a 1/4" x 1/4" square-notch trowel. Larger tiles require larger trowel notches and more thinset. A 50-lb bag of thinset typically covers 60-75 square feet.
Does tile pattern affect how many tiles I need?
Yes. A standard grid pattern is the most efficient with minimal waste. Running bond (brick pattern) adds about 2% waste due to offset cuts. Diagonal and herringbone patterns add about 5% waste because more tiles need to be cut at angles along the edges. Our calculator automatically adjusts for pattern waste.
How much does tile installation cost?
Tile material costs range from $1-15 per square foot depending on type (ceramic, porcelain, natural stone). Professional installation typically adds $5-15 per square foot for labor. Budget an additional $1-3 per square foot for thinset, grout, and supplies. Our calculator estimates material cost based on your price per square foot input.