Tile Calculator (Quantity + Wastage)

Tile estimation looks simple - measure the room, divide by the tile area - but in practice it rarely works out cleanly. Edges need cuts, cuts produce waste, patterns like diagonal and herringbone multiply the waste, and the result is almost always "just a few tiles short" if you order the bare minimum. The Tile Calculator handles all of this: it sums the area of one or many rooms, factors in the layout pattern, adds a wastage percentage, and converts the result into whole boxes with a price estimate.

Pick a tile size preset or enter custom dimensions, set the layout pattern (straight, diagonal or herringbone), choose your wastage allowance, and add the rooms you are tiling. The calculator gives you total tiles needed, total boxes to order, total cost, and a per-room breakdown so you can see exactly which room drives the order. The learning section below explains the underlying formulas, why certain patterns need more wastage, how to read tile specifications, and how to avoid the most common ordering mistakes.

The tile estimation formula has four steps: (1) compute the room area, (2) compute the tiles per m2, (3) add the wastage allowance, and (4) round up to whole boxes. The math is straightforward but each step has a small twist that affects the final count.

Step 1 - Room area. For a rectangular room, multiply length by width. For L-shaped or U-shaped rooms, break them into rectangles, sum each, then add. The calculator does this automatically when you add multiple rooms. All areas are in square metres for metric or square feet for imperial; the calculator converts internally as needed.

Step 2 - Tiles per m2. This is the reciprocal of the area of one tile plus its grout joint. For a 600x600 mm tile with a 3 mm grout joint, the effective tile size is 0.603 x 0.603 m, giving 1 / (0.603 x 0.603) = 2.75 tiles per m2. The grout joint is small but matters: a 5 mm joint instead of 2 mm reduces the tile count by about 1%, which on a large job is several boxes.

Step 3 - Wastage allowance. The base wastage depends on the room shape and the installer skill. 5% is the absolute minimum for a rectangular room with an experienced tiler. 7% is the standard for most residential work. 10% accounts for corners, pillars and moderately complex shapes. 15% is for diagonal lay or complex shapes. 20% is for herringbone or very complex layouts. The calculator lets you set this directly.

Step 4 - Round up to boxes. Divide the total tiles by tiles-per-box and round up. Most 600x600 mm tiles come 4 per box (covering about 1.44 m2 including joints). Most 300x300 mm tiles come 12 per box. Always round up - half a box is not orderable, and you will use the leftover for cuts and future repairs.

The final formula is: total boxes = ceil((room_area x tiles_per_m2 x (1 + wastage)) / tiles_per_box). For a 30 m2 room with 600x600 mm tiles, 7% waste, 4 tiles per box: ceil((30 x 2.75 x 1.07) / 4) = ceil(22.07) = 23 boxes.

How the calculator works

• Six tile size presets: 300x300, 300x600, 450x450, 600x600, 600x1200, plus a fully custom mode in mm.
• Three layout patterns: Straight (default 7% waste), diagonal (+8% extra), herringbone (+13% extra) - automatically adjusts wastage.
• Multi-room support: Add as many rooms as needed, each with its own length, width, and floor/wall flag.
• Configurable wastage: 5% / 7% / 10% / 15% / 20% presets plus a custom value for special cases.
• Grout joint aware: 2 to 5 mm joint width affects the tiles-per-m2 count automatically.
• Box-aware ordering: Auto-calculates tiles per box from tile size, then rounds up to whole boxes.
• Per-box or per-m2 pricing: Switch between the two common retail pricing models.
• Multi-currency: USD, INR, EUR, GBP, AUD, CAD or custom symbol for the cost estimate.
• Three export formats: Plain text summary, CSV line-items, JSON full breakdown - all copyable and downloadable.
• Live preview: All results update as you type - compare two tile sizes or patterns before ordering.
• Learning guide: Rich content section covering formulas, grout standards, PEI ratings and ordering strategy.
• Free and private: No account, no upload, nothing leaves your browser.

Step by step

1. Pick your unit system. Metric (m, m2) or Imperial (ft, ft2) - all calculations update instantly when you switch.
2. Select a tile size preset. 300x300, 300x600, 450x450, 600x600, 600x1200, or Custom for unusual sizes.
3. Set the grout joint. 2 mm for rectified porcelain, 3 to 5 mm for ceramic, 4 to 6 mm for natural stone.
4. Choose a layout pattern. Straight for simple rooms, diagonal for visual interest, herringbone for classic patterns.
5. Set base wastage. 7% for straight lay, 10% for diagonal, 15% for herringbone - the calculator adds pattern waste on top.
6. Add rooms. Click "Add room" for each space, enter length and width, and pick floor or wall.
7. Choose pricing model. "Per box" if your supplier quotes per box, "per m2" for trade or natural stone pricing.
8. Enter tile price. Either price per box or price per m2, depending on your selection above.
9. Pick currency. USD, INR, EUR, GBP, AUD, CAD or a custom symbol for your local currency.
10. Review the result. Total tiles, total boxes, total cost - all in the sticky panel on the right.
11. Export the order. Plain text to share with your supplier, CSV for spreadsheet import, JSON for further processing.

Worked examples

Example 1 - A simple bathroom floor. A 2.4 m x 3 m bathroom with 600x600 mm tiles in a straight lay. Room area: 7.2 m2. Tiles per m2: 2.78. Tiles needed: 20. With 7% waste: 22 tiles. With 4 tiles per box: 6 boxes. At $40 per box: $240. You can complete the job in one day with a single box of spare tiles for future repairs.

Example 2 - An L-shaped kitchen. A 4 m x 3 m main area with a 1.5 m x 1.5 m bump-out, totalling 14.25 m2. With 300x300 mm tiles in a straight lay, you need 158 tiles (11.11 per m2 x 14.25 m2). With 10% waste for the L-shape corners: 174 tiles. At 12 tiles per box: 15 boxes. At $25 per box: $375.

Example 3 - Diagonal hallway. A 1.5 m x 8 m hallway using 600x600 mm tiles laid diagonally. Area: 12 m2. Straight lay would need 34 tiles. Diagonal adds 8% for pattern waste plus 5% for the long narrow shape: 14% total waste. Total tiles: 39. At 4 per box: 10 boxes. At $45 per box: $450.

Example 4 - Herringbone feature wall. A 4 m x 2.4 m living room feature wall using 600x1200 mm tiles in herringbone. Area: 9.6 m2. Tiles per m2: 1.39. Tiles needed: 14. With 15% waste for herringbone: 16 tiles. At 2 per box: 8 boxes. At $80 per box: $640.

Example 5 - Multi-room whole-house job. Three bedrooms (3.5 x 4 m each), two bathrooms (2.5 x 3 m each), a kitchen (4 x 5 m), and a living area (5 x 6 m) - all using 600x600 mm floor tiles. Total area: 42 + 15 + 20 + 30 = 107 m2. Tiles needed at 2.78 per m2: 298. With 7% waste: 319. At 4 per box: 80 boxes. At $40 per box: $3,200 for the entire house.

Example 6 - Comparing tile sizes. Run the same 30 m2 living area calculation twice: once with 600x600 mm tiles (84 tiles, 21 boxes, easier to lay, more grout lines) and once with 600x1200 mm tiles (42 tiles, 21 boxes, faster to lay, fewer grout lines, more expensive per box). The total boxes come out similar but the look and labour differ significantly.

Why use this calculator

• Stop running short mid-job: The pattern-aware wastage adjustment means you order enough for the layout you actually plan, not just the area you are covering.
• Compare tile sizes instantly: Run the same room calculation with 300x300 vs 600x600 vs 600x1200 to see how the box count, cost and visual rhythm change.
• See the cost in your currency: Multi-currency support with custom symbol option for accurate local pricing.
• Handle multi-room jobs cleanly: Add a kitchen, two bathrooms, a hallway and a living room - get one consolidated order with per-room breakdown.
• Understand the formula: The learning section explains why diagonal lay needs 15% and herringbone needs 20%, so you can defend the wastage figure to your client or contractor.
• Export the order list: CSV for spreadsheet import, JSON for further processing, plain text for sharing with your tile supplier.
• Free, private, no signup: All calculations run in your browser, nothing is uploaded.

Tile sizes are usually given in millimetres for metric markets and inches for US markets. The most common residential sizes fall into a few standard categories, each with different visual effects, installation costs, and wastage rates.

• 300 x 300 mm (12 x 12 in): The classic small floor tile. Easy to cut, forgiving of slightly uneven substrates, and the smaller format suits small bathrooms. About 11 tiles per m2. Usually 12 per box.
• 300 x 600 mm (12 x 24 in): A modern mid-size tile, often used for wood-look planks or rectangular layouts. About 5.5 tiles per m2. Usually 6 to 8 per box.
• 450 x 450 mm (18 x 18 in): Less common, but used in some European markets. About 4.9 tiles per m2. Usually 5 to 7 per box.
• 600 x 600 mm (24 x 24 in): The most popular modern floor tile. Faster to lay than smaller tiles, fewer grout lines, modern look. About 2.78 tiles per m2. Almost always 4 per box.
• 600 x 1200 mm (24 x 48 in): Large format, premium look. About 1.39 tiles per m2. Usually 2 per box. Requires a perfectly level substrate.
• 800 x 800 mm (32 x 32 in): Large format for commercial and high-end residential. About 1.56 tiles per m2. Usually 2 to 3 per box.
• 1200 x 1200 mm (48 x 48 in): Extra-large format, used in commercial lobbies and high-end residential. About 0.69 tiles per m2. Usually 1 to 2 per box.
• Custom sizes: Many manufacturers offer sizes outside the standard set - 200 x 600 mm wood-look planks, 100 x 100 mm mosaics, hexagonal tiles, and others. Use the Custom mode in the calculator to enter your specific dimensions.

When choosing a tile size, consider the room dimensions. A very small bathroom with 600x600 mm tiles will only fit 2 or 3 tiles across the floor, making the room look chopped up. A very large living room with 300x300 mm tiles will have so many grout lines that the floor looks busy. The general rule: the larger the room, the larger the tile.

Grout is the cement-based or epoxy material that fills the joints between tiles. The right grout width and type depends on the tile material, the room usage, and the desired visual effect.

• Un-sanded cement grout: For joints 1 to 3 mm wide. Used with rectified porcelain and ceramic tiles where narrow joints are desired. Easier to apply but less durable than sanded grout in wide joints.
• Sanded cement grout: For joints 3 to 10 mm wide. The standard for most residential floor tile installations. The sand adds strength and resists shrinkage cracking.
• Epoxy grout: For joints 1.5 to 12 mm wide. Stain-proof, chemical-proof, and waterproof. Used in commercial kitchens, hospitals, and high-end residential. More expensive and harder to work with than cement grout.
• Urethane grout: Pre-mixed, flexible, and stain-resistant. A good middle ground between cement and epoxy for residential use.

Standard grout joint widths by tile type:

• Rectified porcelain: 2 to 3 mm. The near-seamless look requires careful tile selection and a skilled installer.
• Standard ceramic floor tile: 3 to 5 mm. The most common choice for residential floors.
• Natural stone (marble, granite, travertine): 2 to 4 mm for polished, 4 to 6 mm for tumbled or honed.
• Mosaic tiles: Usually come on mesh sheets with 2 to 3 mm joints between sheets.
• Wood-look plank tiles: 2 to 3 mm for a tight fit, up to 5 mm for a more rustic look.

The grout joint affects the tiles-per-m2 count by about 1 to 2%. For a 600x600 mm tile, a 2 mm joint gives 2.75 tiles per m2, while a 5 mm joint gives 2.67 tiles per m2 - a 3% difference. On a 50 m2 job, that is about 4 fewer tiles with the wider joint, but the grout material cost is about 30% higher.

Always seal cement-based grout after it has cured (typically 28 days). Unsealed grout absorbs stains and water, leading to discoloured joints and potential water damage to the substrate. Epoxy and urethane grouts do not need sealing.

The layout pattern affects both the visual appearance and the tile wastage. The three main patterns have very different waste profiles.

• Straight lay (stack bond): All tiles aligned in a grid. The fastest to lay and the most material-efficient. Only the tiles along the room edges need cuts. Wastage: 5 to 7%.
• Offset / brick bond: Each row offset by half a tile from the row below. The classic subway-tile look. Slightly more cuts than straight lay because the offset means every other row starts with a half tile. Wastage: 7 to 10%.
• Diagonal (45-degree): All tiles rotated 45 degrees from the room walls. The most common decorative pattern for floors. Every edge tile needs a 45-degree cut, generating triangular offcuts that may or may not be usable depending on the layout. Wastage: 12 to 15%.
• Herringbone: Rectangular tiles laid in an L-shape pattern, alternating direction by 90 degrees. A classic pattern dating back to Roman roads. Every tile end needs a cut. Very material-intensive. Wastage: 15 to 20%.
• Chevron: Similar to herringbone but the tiles are cut at 45 degrees on the ends so they meet at a point. Less material than herringbone because no end tiles need to be cut, but the cut tiles themselves are more wasteful. Wastage: 12 to 18%.
• Versailles / French pattern: A combination of 4 or 5 different tile sizes laid in a repeating pattern. The most decorative but also the most material-intensive. Wastage: 18 to 25%.

For complex patterns, the wastage allowance is the single biggest factor in the order quantity. A 30 m2 room with herringbone needs about 20% more tiles than the same room with straight lay - on a $40/box job, that is about 4 extra boxes, or $160 extra. Under-ordering on a herringbone job is a common reason for last-minute trips to the tile shop, and the second-batch tiles are almost never an exact match.

Pattern waste comparison