How much waste should I add for tile?

About 10 percent for a standard straight layout. Use 15 percent for a diagonal or herringbone pattern, or for a room with many cuts around fixtures and corners.

How much thinset do I need?

A 50 pound bag of thinset mortar covers roughly 40 to 60 square feet depending on the trowel and tile size, so plan on about one bag per 50 square feet. Larger tiles and bigger trowels use more.

Should I buy tile from the same lot?

Yes. Tile color can shift slightly between production lots, so buy all you need at once, including the waste, from a single lot or batch number to keep the color consistent.

Home / Tile Calculator

Tile Calculator

A tile calculator tells you how many tiles a floor or wall needs, plus the thinset and the cost. It takes the area, the tile size, and a waste allowance, and returns the tile count and materials. Type the area below and pick a tile size. Everything runs in your browser, with no signup.

Updated for 2026

Your area

Enter the area and pick a tile size. Results update instantly.

Tile size

Length

Width

Waste allowance

Tile price

$/ ft²

Tiles to buy

Area

0 ft²

With waste

0 ft²

Thinset (50 lb bags)

Tile cost

Each tile covers

0 ft²

Tiles needed by tile size

Tiles for a 120 ft² area with 10% waste. Tap a row to load that tile size.

Tile size	Each covers	Per ft²	Tiles (120 ft²)

How the tile count is calculated

Each tile covers its width times height in inches, divided by 144 to get square feet. Divide the area, with a waste allowance, by that to get the tile count:

Tiles = Area × (1 + Waste) ÷ ( Tile width × Tile height ÷ 144 )

A 12 by 12 inch tile covers exactly 1 square foot. Add 10 percent waste for a straight layout, or 15 percent for diagonal or herringbone. Allow about one 50 pound bag of thinset per 50 square feet. Buy all the tile at once from a single lot so the color stays consistent.

Worked example (Stand: 2026)

Area10 ft × 12 ft
Area (10 × 12)120 ft²
Tile12 x 12 in (1 ft² each)
Waste allowance10%
Area with waste (120 × 1.10)132 ft²
Tiles (132 ÷ 1)132 tiles
Thinset (120 ÷ 50)3 bags
Tile cost (132 × $4.00)$528

Frequently asked questions

How many tiles do I need?

Divide the area, with a waste allowance, by the square feet each tile covers. The calculator above does this for any tile size and also gives the thinset and cost.

How much waste should I add?

About 10 percent for a straight layout, 15 percent for diagonal or herringbone, and a bit more for a room with lots of cuts around fixtures.

How much thinset?

Roughly one 50 pound bag per 50 square feet, more for large format tile and bigger trowels. Check the bag for the coverage with your trowel size.

Why buy from one lot?

Tile color shifts slightly between production lots. Buy everything, including the waste, from one lot or batch so the finished surface is an even color.

Does this calculator store my numbers?

No. Everything is calculated in your browser. Nothing you enter is sent to a server or saved.

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