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Tile Calculator
Find out how many tiles and boxes you need for a floor, wall or backsplash, with waste for your layout pattern and the grout to buy.
YOU NEED
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Estimate only. Bag yields, material density and waste vary by product and supplier. Confirm quantities with your supplier and check local building codes before you buy or build.
How to calculate how many tiles you need
Divide the room area by the area of one tile, including the grout joint. A 12 × 10 ft room is 120 square feet, and 12 inch tiles with a 1/8 inch joint need 118. Then add waste for cuts and mistakes, which makes 130 at 10%.
How much extra tile to buy
Plan about 10% extra for a straight lay, 15% for diagonal and 18% for herringbone, because angled cuts waste more tile. Add a few percent more for rooms with alcoves or many obstacles, and for a first tiling job. Keep leftover tile for repairs, since colors vary between batches.
Grout and joint width
Grout needs depend on the tile size, joint width and tile thickness. Narrow joints on large tiles use little grout, while wide joints on small tiles use a lot. The calculator adds 10% for waste and uneven subfloors and shows how many bags to buy.
Frequently asked questions
How much extra tile should I buy?
Buy 10% extra for a straight pattern, about 15% for diagonal and 18% for herringbone. Rooms with many cuts or a first-time installer should add a few percent more.
How many 12x12 tiles do I need for a 100 sq ft room?
With no grout joint it is 100 tiles. With a 1/8 inch joint it is 98, and with 10% waste you buy 108, or 9 boxes of 12.
How do I figure out how many boxes of tile to buy?
Divide the tiles you need, with waste, by the tiles per box and round up. The box label shows the coverage in square feet, so you can also divide by that.
Does the calculator include the grout joint?
Yes. Enter the joint width, for example 1/8 or 3/16 inch, and the tile pitch includes it. Enter 0 to ignore the joint.
Is this a flooring calculator?
Yes, it works for tile flooring in any room. For wood, vinyl or laminate planks, use the same room measurements and enter the plank size, and use the pattern waste as a guide.
Can I use it for walls and backsplashes?
Yes. Enter the wall height as the width. Subtract windows or outlets only if they are large, since small cutouts are covered by waste.
How accurate is this estimate?
It is a planning estimate, not an order. Bag yields, material density and waste vary by product, supplier and job, so confirm quantities with your supplier and check local building codes before you buy or pour.
Are my measurements saved?
No. Everything is calculated in your browser. Nothing is uploaded or stored.
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Also on this topic: Tile square footage calculator, Tile installation cost calculator.