Floor Tile Calculator

How to measure a floor for tile

Floor tiling almost always starts the same way: get the square footage right, and everything after it falls into place. Run a tape measure along the longest wall for the length, then across for the width, and multiply the two. If the room isn’t a clean rectangle — say a kitchen that opens into a dining nook — break it into rectangles you can measure and add them up.

Worked example: a 12 × 10 ft kitchen floor

Here’s the whole thing start to finish for a typical kitchen using standard 12×12 inch tiles:

Larger-format tiles like 12×24 or 24×24 cut the tile count dramatically and leave fewer grout lines, but they need a flatter subfloor to sit right. Our full floor-tile guide walks through tricky shapes, and the cost-to-tile-a-floor guide covers the budgeting side.

A few things worth knowing before you buy

Buy all your tile from the same production batch (the dye lot is printed on the box) so the colour matches across the floor. Keep a box or two spare — tiles get discontinued, and a cracked tile in year three is far easier to swap when you already have the match on a shelf. If you’re going diagonal or herringbone, bump your waste allowance up, because the perimeter cuts eat more tile than a plain grid does. For the detail on that, see how much extra tile to buy.

Frequently Asked Questions

How do I calculate how many floor tiles I need?

Measure the room's length and width in feet and multiply them for the floor area. Divide that by the area of one tile, then add 10% for waste and round up to whole boxes. The calculator above does all of this the moment you type in your numbers.

How many 12x12 tiles do I need for a 12x12 room?

A 12x12 foot room is 144 square feet, and a 12x12 inch tile covers 1 square foot, so you need 144 base tiles. Add 10% for waste and you're buying around 159 tiles — then round up to full boxes.

How do I calculate tiles for an L-shaped floor?

Split the L into two rectangles, work out each one on its own, and add the areas together. The calculator has an "add another area" option so you can enter both rectangles and get a single combined tile count.

Should I buy extra floor tile?

Yes — always. Plan on about 10% extra for a straight or grid layout, and closer to 15% for diagonal or herringbone floors because the edge cuts are less forgiving. The leftovers double as spares if a tile ever cracks years down the line.

Tiling a different surface?

The math behind every tile estimate is the same — area, tile size, grout gap, and a waste buffer. These versions just come preset for a specific job, with tips and worked examples for that surface. Pick whichever is closest and the numbers come out the same.