Tile Calculator

Enter your room dimensions, tile size, and layout pattern below to calculate how many tiles to order. The pattern you choose changes your waste factor more than almost any other decision in the project.

Room length (ft)

Room width (ft)

Tile length (in)

Tile width (in)

Layout pattern

Straight lay (10%)Diagonal (45°) (15%)Herringbone / chevron (20%)Mosaic / basketweave (20%)

Room area

120.0 sq ft

Bare tiles (no waste)

30

Waste factor (Straight lay)

10%

Tiles needed

33

Tiles needed already rounds up to the nearest whole tile. Manufacturers sell by the box, so round up again to your box coverage before ordering. The Tile Council of North America also recommends budgeting an additional 2–5% for shipping and handling breakage on top of this layout waste factor.

Installing laminate, vinyl plank, or hardwood instead? Use our flooring calculator instead. It’s built around box coverage rather than individual tile counts.

Step 1: Calculate Bare Coverage

Tiles needed = Room Area ÷ Tile Area

Example: A 120 sq ft bathroom floor using 2 ft × 2 ft (4 sq ft) tiles.

120 ÷ 4 = 30 tiles for bare coverage, before any waste factor.

Tile is one of the few materials where the nominal size is close enough to the actual size that you can work from it directly. The grout joint is absorbed by the module: a 12 × 12 tile with a 1/8 in joint occupies 12.125 in of run, and over a room that accumulates, but it accumulates into the field rather than changing the tile count. You finish with a slightly narrower cut at the wall, not an extra tile.

Tiles per 100 Square Feet

Tile Size	Area Each	Tiles per 100 sq ft
4 × 4 in	0.11 sq ft	900
6 × 6 in	0.25 sq ft	400
8 × 8 in	0.44 sq ft	225
12 × 12 in	1.00 sq ft	100
12 × 24 in	2.00 sq ft	50
18 × 18 in	2.25 sq ft	45
24 × 24 in	4.00 sq ft	25
24 × 48 in	8.00 sq ft	13

Tile sold in metric sizes does not convert to these cleanly. A 300 × 300 mm tile is 11.8 in, not 12, so a “12 inch” metric tile covers about 3% less area than an imperial one. Over a large floor that is a tile or two, and it is a common reason a count taken from an imperial table comes up short.

Tile Size	Area Each	Tiles per 10 m²
200 × 200 mm	0.04 m²	250
300 × 300 mm	0.09 m²	112
300 × 600 mm	0.18 m²	56
450 × 450 mm	0.20 m²	50
600 × 600 mm	0.36 m²	28
600 × 1200 mm	0.72 m²	14

Step 2: Apply the Waste Factor for Your Layout Pattern

This is the step that matters most, and it’s where flat “add 10%” advice falls short:

Layout Pattern	Waste Factor	Why
Straight lay (parallel to walls)	10%	Fewest cuts, since only perimeter tiles need trimming
Diagonal (45° to walls)	15%	Every wall meets tile at an angle, doubling the triangular perimeter cuts
Herringbone / chevron	18–20%	Every tile intersection requires precise angled cuts to align
Mosaic / basketweave	18–20%	Complex pattern alignment across the whole field

Continuing the example: 30 tiles, straight lay pattern.

30 × 1.10 = 33 tiles → round up to full boxes

If you switched to herringbone for the same room: 30 × 1.20 = 36 tiles, a meaningful jump for the same square footage, purely from the pattern choice.

Step 3: Round Up to Full Boxes

Tile is sold by the box, and manufacturers rarely sell partial boxes. Always round your final tile count up to the nearest full box, and check whether your project also needs breakage allowance. The Tile Council of North America puts ceramic tile breakage at an additional 2–5% for shipping and handling damage, on top of your layout waste factor. Our material waste factors guide covers how that allowance compares with other materials, and why tile needs attic stock on top of it.

Versailles and Other Multi-Size Patterns

The Versailles pattern, also sold as French pattern, does not fit the arithmetic above, because it is not one tile size. It uses four sizes laid in a fixed repeating module, and the whole point of the pattern is that the four sizes appear in set proportions.

This changes how you order. Suppliers sell the pattern as a pre-proportioned kit covering a stated area, not as loose tiles, and you calculate how many modules cover your room rather than how many tiles. Buying the four sizes separately and guessing the ratio is the classic way to finish with a surplus of the large format and a shortage of the small one, neither of which is usable.

Two practical consequences:

• Waste sits around 10–15%, lower than herringbone despite looking more complex, because the module absorbs variation internally and only the perimeter gets cut.
• A partial module at the perimeter cannot be improvised. Cutting a large tile down to stand in for a small one breaks the pattern visually, since the layout depends on the size relationships. Order a full extra module rather than planning to cut your way out.

The same logic applies to any modular multi-size pattern. If the tile is sold as a set, estimate in sets.

Wall Tile, Trim, and Skirting

Wall tile follows the same area arithmetic, with two differences that catch people out.

Openings are not always deductions. A shower niche adds tiled surface rather than removing it. The back and four returns are all tiled. Subtracting the niche opening from your wall area and forgetting to add the interior is a reliable way to run short. Small deductions are usually not worth taking at all: most installers ignore anything under about 10 sq ft, because the cuts around an opening generate offcuts that the deduction assumes you will reuse, and you generally cannot.

Trim is a linear measurement, not an area one. Bullnose, pencil trim, and skirting are counted along the exposed edge:

Trim pieces = Total exposed edge length ÷ Length of one trim piece

Round up, then add roughly 10%. Trim is more fragile than field tile and the cuts at corners are less forgiving. Measure the edges that will actually be exposed: a shower surround needs trim on its outside vertical edges and top, but not where it meets the floor or an adjacent tiled wall.

For floor skirting, measure the room perimeter and subtract door openings, then divide by the piece length.

A Note on L-Shaped or Irregular Rooms

Waste percentages assume a simple rectangular room. Add an alcove, island, or L-shaped layout, and waste climbs further. A herringbone pattern in an L-shaped room can push past 20%, since every additional corner creates another run of triangular offcuts. For irregular rooms, measure and calculate each rectangular section separately rather than trying to average one waste factor across the whole space.