Tile & Flooring Calculator

How the Tile & Flooring Calculator works

If you have ever stood in a room wondering how much tile you need, this tool gives you a fast, reliable answer. Enter the room's length and width in feet, the face dimensions of one tile in inches, and the layout pattern you plan to use. Pick whether tiles come by the box and how many are in each box, and the calculator returns the total tiles required, the number of full boxes to buy, and the room's square footage.

Under the hood it works in two areas. First it figures the room area from length times width. Then it figures the area of a single tile and divides one into the other to get a raw piece count. On top of that it adds a waste allowance for the cuts you will inevitably make at the walls, and finally rounds up to whole boxes so you order what a tile shop actually sells.

The same approach works for ceramic, porcelain, natural stone, and wood-look planks. Whether you are tiling a bathroom floor, a kitchen backsplash, or a whole open-plan living area, the flooring calculator treats it as area to cover divided by the area each piece covers.

How to calculate how much tile you need by hand

The math is simple once you keep your units straight. Start with the room area: multiply length by width, both in feet, to get square feet. A 12 by 10 ft room is 120 sq ft.

Next find the area of one tile. Tile sizes are given in inches, so multiply the tile width by the tile length and divide by 144 to convert square inches to square feet. A 12 by 24 in tile is 288 square inches, which is 2 square feet.

Now add waste. A straight grid layout wastes about 10%, a diagonal layout about 15%, and herringbone or other complex patterns about 20%, because angled and offset cuts leave more unusable offcuts. Multiply your room area by one plus that percentage. For 120 sq ft on a diagonal layout that is 120 times 1.15, or 138 sq ft of coverage to buy.

Divide the coverage by the area of one tile and round up: 138 divided by 2 is 69 tiles. Finally divide tiles by the count per box and round up again to get whole boxes. That rounding is why the count from this tool may run slightly above a back-of-napkin figure.

Tips for an accurate tile take-off

A clean estimate starts with clean measurements and a realistic view of how tile gets cut on a real job.

• Measure each room at floor level and in two spots — walls are rarely perfectly square, so use the larger number.
• Subtract large built-ins like a kitchen island or a tub footprint; leave small obstructions in as built-in safety margin.
• Match the waste percentage to your real layout — do not use the 10% straight figure if you are running a 20% herringbone pattern.
• Always buy full boxes from the same dye lot, and keep a spare box for future repairs since colors shift between production runs.
• For large-format tile and long planks, expect more breakage during cuts and consider nudging the order up by an extra box.

From tile count to a priced estimate

A material take-off is only half the job — the client wants a number. GreenlitBid turns a takeoff like this into a priced, client-ready line item: it pairs the tile, thinset, grout, and labor hours with your rates so a tiled floor becomes a clear figure in a professional estimate instead of a sticky note.