How much waste should I include?

For simple, straight‑lay patterns in rectangular rooms, 5–8% waste is often sufficient. For diagonal layouts, herringbone, or rooms with lots of corners, niches, and obstacles, 10–15% or more may be appropriate. Always consider your layout, skill level, and the difficulty of cuts when choosing a waste percentage.

Should I round up to full boxes?

Yes. After the calculator gives you a tile count, divide by tiles‑per‑box and round up to the next whole box. Keeping a few extra tiles is wise for future repairs, especially since dye lots and product lines can change over time.

How do I handle a shower niche or doorway?

You can subtract the square footage of large openings (like big niches, windows, or doorways) from your room area if you want a tighter estimate. Alternatively, you can leave them in and use a slightly lower waste percentage, treating those openings as part of your built‑in waste allowance.

Can I mix tile sizes or patterns with this calculator?

This calculator assumes a single tile size and pattern. For mixed‑size patterns or multi‑pattern projects, calculate each tile size and pattern section separately, then add the results, or consult a pattern‑specific layout guide from the manufacturer.

Does this calculator account for grout joint width?

Not explicitly. For most standard grout joints (for example, 1/16" to 1/4"), the impact on tile count is small, and the waste percentage typically covers the difference. For ultra‑precise layouts or large format tiles with tight joints, you can refine area measurements manually if needed.

construction calculator

Tile Calculator

Determine tile counts and total area including waste.

Results

Tiles needed: 165.00
Total area (sq ft): 150.00

Overview

Running short on tile in the middle of a job can derail your schedule, risk dye‑lot mismatches, and force you to change patterns to make things work. Over‑ordering, on the other hand, ties up cash and leaves you with heavy, fragile boxes to store or return.

This tile calculator helps you hit the sweet spot by turning simple room and tile dimensions into a clear estimate of how many tiles you need, including a practical waste allowance. By entering the room length and width in feet, tile dimensions, and a waste percentage for cuts, offcuts, and breakage, you get a recommended tile count and total coverage area that you can convert into boxes when ordering.

How to use this calculator

Measure or confirm the length and width of the floor or wall area you plan to tile, in feet. For irregular rooms, approximate the main area as a rectangle or break it into rectangles and sum the areas.
Enter the Room length and Room width in feet.
Convert your tile size into feet if necessary (for example, 12" × 12" tile = 1 ft × 1 ft; 24" × 12" tile = 2 ft × 1 ft) and enter those values as Tile length and Tile width.
Choose a Waste % based on the pattern and complexity of the installation: lower for straight lay in a simple room, higher for diagonals, herringbone, or rooms with lots of cuts.
Review the Tiles needed output as your base tile count including waste. Round this number up to the next whole tile and then convert it into boxes using your tile’s box coverage or tiles‑per‑box information.
Use the Total area (sq ft) output to compare with box coverage labels or to allocate tile across multiple rooms or design areas.

Inputs explained

Room length/width: The dimensions of the area to be tiled in feet. Measure the longest length and width of the room or wall. For L‑shaped or irregular spaces, break the area into rectangles, calculate each, and add them together, or use the largest bounding rectangle and a higher waste percentage.
Tile length/width: The size of a single tile in feet. If your tiles are labeled in inches (for example, 12" × 24"), convert to feet (1 ft × 2 ft) before entering. Enter the face dimensions of the tile, not including grout joints, since grout spacing is generally small compared to tile size.
Waste %: The extra percentage of tile you want to add to cover cuts at edges, pattern repeats, layout adjustments, and breakage. Straight‑lay floors in simple rectangular rooms might use 5–8% waste, while diagonals, herringbone patterns, or rooms with lots of jogs and obstacles may need 10–15% or more.

Outputs explained

Tiles needed: The estimated number of tiles required to cover the room area, including your chosen waste percentage. Use this as a base tile count, then round up to full boxes when ordering.
Total area (sq ft): The total square footage of the area you’re tiling, calculated from room dimensions. This is helpful for cross‑checking box coverage and for comparing tile options that list coverage in square feet per box.

How it works

We start by treating the tiled area as a rectangle. Room area in square feet is calculated as: Room area = Room length (ft) × Room width (ft).

Next, we calculate the area of a single tile in square feet. Tile area = Tile length (ft) × Tile width (ft). If your tiles are measured in inches, you convert inches to feet before entering (for example, 12 in = 1 ft, 18 in = 1.5 ft).

The theoretical number of tiles needed with no waste is Room area ÷ Tile area.

You then choose a waste percentage to account for cuts at edges, pattern alignment, broken tiles, and future repairs. Waste% is converted into a multiplier: Waste multiplier = 1 + Waste% ÷ 100.

We multiply the no‑waste tile count by the waste multiplier to get Tiles needed including waste. This output is shown as a decimal; in practice, you round up to a whole tile and then up again to full boxes as required.

We also report the Total area in square feet so you can cross‑check against box coverage information or combine multiple areas in a larger project.

Formula

Room area (sq ft) = Room length (ft) × Room width (ft)\nTile area (sq ft) = Tile length (ft) × Tile width (ft)\nBase tiles (no waste) = Room area ÷ Tile area\nTiles needed = Base tiles × (1 + Waste% ÷ 100)

When to use it

Estimating tile purchases for floors, walls, showers, tub surrounds, or kitchen backsplashes without having to manually compute square footage and tile counts.
Comparing how different tile sizes and patterns (straight lay vs diagonal vs herringbone) affect waste and total tile count for the same room.
Budgeting projects by turning room dimensions into a tile count and then matching that to box quantities and cost per square foot.
Planning extra tile for future repairs in high‑traffic areas or when using tiles from dye lots that may not be available later.
Helping DIYers and contractors communicate tile needs clearly to suppliers and clients by using consistent, calculated quantities instead of rough guesses.

Tips & cautions

Use a lower waste percentage (around 5–8%) for simple, straight‑lay patterns in rectangular rooms with minimal obstacles, and a higher percentage (10–15% or more) for diagonal, herringbone, or border patterns.
Always confirm tiles‑per‑box and coverage per box from the manufacturer or supplier. After computing Tiles needed, divide by tiles per box and round up to full boxes—you can’t buy partial boxes of most tiles.
Include closets, niches, and small offsets in your room measurements if they will be tiled; these small areas add up and can consume more tiles than expected due to additional cuts.
Tile dye lots and calibrations can vary between production runs. Ordering a bit extra up front reduces the risk of mismatched color or size if you need to buy more later.
Consider layout and grout lines when measuring. For extremely precise layouts, you may want to account for grout joint width and layout starting points, but this calculator is designed for quick planning.
Assumes a simple rectangular area with uniform coverage. Irregular shapes, complex layouts, and multiple rooms require segmenting the space and summing multiple calculations.
Does not automatically subtract large openings (such as big floor registers, large shower benches, or built‑in cabinets). You must subtract their areas manually or include them in waste.
Tile box coverage and tiles‑per‑box vary by product, thickness, and manufacturer; this calculator does not know your specific box size and relies on your adjustments when converting to boxes.
Does not account for pattern repeats, directional grain, or mixing of different tile sizes in a pattern (such as Versailles patterns), which may require a more detailed layout and ordering plan.
Focused on tile count and area only; it does not estimate grout, mortar, backer board, or other installation materials.

Worked examples

Example 1: 150 sq ft room with 12"×12" tiles and 10% waste

Room length = 15 ft; room width = 10 ft → Room area = 15 × 10 = 150 sq ft.
Tile size = 12"×12" → 1 ft × 1 ft → Tile area = 1 sq ft.
Base tiles (no waste) = 150 ÷ 1 = 150 tiles.
Waste% = 10% → multiplier = 1.10.
Tiles needed = 150 × 1.10 = 165 tiles. If tiles come 10 per box, you would order at least 17 boxes.

Example 2: 120 sq ft kitchen with 12"×24" tiles and 12% waste

Room length = 12 ft; width = 10 ft → Room area = 120 sq ft.
Tile size = 12"×24" → 1 ft × 2 ft → Tile area = 2 sq ft.
Base tiles = 120 ÷ 2 = 60 tiles.
Waste% = 12% → multiplier = 1.12.
Tiles needed = 60 × 1.12 = 67.2 → round up to 68 tiles, then round to full boxes based on your product’s tiles‑per‑box.

Example 3: Small bathroom floor with diagonal layout

Room length = 8 ft; width = 5 ft → Room area = 40 sq ft.
Tile size = 8"×8" → 0.667 ft × 0.667 ft → Tile area ≈ 0.444 sq ft.
Base tiles ≈ 40 ÷ 0.444 ≈ 90 tiles.
Because you plan a diagonal layout with many edge cuts, set Waste% = 15% → multiplier = 1.15.
Tiles needed ≈ 90 × 1.15 ≈ 103.5 → round up to 104 tiles and convert to boxes.

Deep dive

This tile calculator converts room dimensions and tile size into an estimated tile count with a built‑in waste allowance for cuts, patterns, and breakage. Enter room length and width, tile dimensions, and a waste percentage to size your tile order before you start setting.

Use it for floors, showers, walls, or backsplashes to avoid reordering mid‑project. Increase waste for complex layouts, then round up to full boxes and keep extra tiles on hand for future repairs and replacements.

FAQs

How much waste should I include?: For simple, straight‑lay patterns in rectangular rooms, 5–8% waste is often sufficient. For diagonal layouts, herringbone, or rooms with lots of corners, niches, and obstacles, 10–15% or more may be appropriate. Always consider your layout, skill level, and the difficulty of cuts when choosing a waste percentage.
Should I round up to full boxes?: Yes. After the calculator gives you a tile count, divide by tiles‑per‑box and round up to the next whole box. Keeping a few extra tiles is wise for future repairs, especially since dye lots and product lines can change over time.
How do I handle a shower niche or doorway?: You can subtract the square footage of large openings (like big niches, windows, or doorways) from your room area if you want a tighter estimate. Alternatively, you can leave them in and use a slightly lower waste percentage, treating those openings as part of your built‑in waste allowance.
Can I mix tile sizes or patterns with this calculator?: This calculator assumes a single tile size and pattern. For mixed‑size patterns or multi‑pattern projects, calculate each tile size and pattern section separately, then add the results, or consult a pattern‑specific layout guide from the manufacturer.
Does this calculator account for grout joint width?: Not explicitly. For most standard grout joints (for example, 1/16" to 1/4"), the impact on tile count is small, and the waste percentage typically covers the difference. For ultra‑precise layouts or large format tiles with tight joints, you can refine area measurements manually if needed.

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This tile calculator estimates tile counts based on user-entered room dimensions, tile size, and a simple waste percentage. It assumes rectangular areas, a single tile size, and uniform coverage. Actual tile needs can vary based on layout, pattern, grout joint width, cutting efficiency, and breakage. Always verify measurements on site, review tiles‑per‑box and coverage details from your manufacturer, and consider consulting with a tile professional or supplier—especially for complex patterns or large projects—before finalizing your order.