Tile Quantity Calculator
Turn area, tile size and pattern into tiles and boxes
Tile quantity and box estimate FAQ
Do I enter room dimensions or total area?
This calculator expects a total tiled area. You can either measure each wall or floor, multiply length × width, and then add the areas together, or use a separate square footage tool and paste the result. Subtract large openings like doors or picture windows before you enter the final area.
How accurate are the tile counts without grout lines?
Grout joints slightly increase coverage per tile, but cuts, breakages and layout decisions tend to eat that back up. To keep the form simple and conservative, this tool ignores grout width and relies on the pattern waste factor to cover small differences.
What pattern should I choose?
Use Straight / grid when tiles are aligned in a simple grid, Brick / offset for half-offset or running bond layouts, and Diagonal / herringbone for layouts that spin tiles at an angle or interlock. Stepped or chevron patterns usually behave like the diagonal group for waste.
Is the waste allowance enough for my project?
For simple, open rooms with a straight pattern, 10% is often fine. Tight bathrooms, lots of corners, niche shelves, thresholds or diagonal layouts often need 12–15%. If your tiler prefers a higher waste figure, use these numbers as a minimum and follow their guidance.
How should I use tiles per box?
Look on the packaging or product page for tiles per box. Enter that number to convert tile counts into boxes and round up. If you skip this field, the calculator still tells you how many tiles you need, and your supplier can translate that into boxes on their end.
What if my floor slopes or walls are out of square?
The math here assumes straight, square geometry. Real rooms with waves, slopes and skewed corners can chew up more tile as you tighten joints and adjust layout. In those cases, use this tool as a baseline and then bump waste higher based on your tiler’s experience.
Can I mix boxes from different dye lots?
Ideally, no. Even small differences between dye lots or production runs can show on a big floor or wall. Use this calculator to land close on quantity, then make sure all boxes you buy share the same lot number. Keep sealed spare boxes in case a few tiles need replacing later.
Should I keep leftover tiles after the job?
Keeping a small stack of matching spare tiles is usually wise for future repairs, changes in fixtures or accidental damage. If your supplier has a good return policy, consider returning just the last unopened box and keeping the partial one.
How to use this tile quantity calculator
This calculator turns a simple area + tile size + pattern input into tile counts, waste and box estimates. The aim is to keep the form small while still protecting you from last-minute “almost the same shade” replacement runs.
1. Choose units and enter total tiled area
Start with the units you’re most comfortable with: ft² for US-style plans or m² for metric. Add up the area of every surface you plan to tile (walls, floors, shower niches, splashbacks) and enter the total. If you already have a take-off from a square footage calculator, you can simply paste that number here.
2. Enter tile length and width
Next, type the finished tile size in inches or centimetres. For example, a 12×24" floor tile is entered as 24 in length and 12 in width, a 600×600 mm tile as 60 cm by 60 cm. The calculator converts these sizes into a per-tile area behind the scenes.
3. Add tiles per box if you want box counts
If your supplier lists tiles per box, enter that number so the tool can show both tiles and boxes. If you leave it blank, you’ll still get tile counts including waste; you can then ask the store to convert tiles into boxes for their particular product.
4. Pick your pattern to set waste
Choose the pattern that matches your layout: a straight grid, a brick-style offset, or a diagonal / herringbone approach. Each choice carries a slightly different waste factor, with more complex patterns getting more spare tiles to cover angled cuts and layout tweaks.
5. Read tiles, waste and boxes
Hit Calculate tiles & boxes to see:
- Area used in your chosen units and the alternate unit.
- Tile area based on your length and width.
- Tiles without waste (raw coverage) and with your pattern waste factor.
- Box count if tiles per box is provided, rounded up so you have enough.
The waste percentage line tells you how much extra tile the pattern is adding, which you can compare with your tiler’s usual rule of thumb.
6. Copy the summary and refine with your tiler
Use Copy summary to drop the numbers into a notes app, email chain or quote spreadsheet. From there you can tweak waste, consider an extra box for future repairs and confirm everything with your tile supplier and installer before ordering.
Treat this as a quick, transparent helper. Final decisions on tile quantity should always match the exact product’s box coverage, advice from your tiler and any special layout details on your project.
How the tile quantity & box math works
The tile math is intentionally straightforward: convert everything into a consistent unit, find area per tile, divide, then add a pattern-based waste factor and convert into boxes if you provide tiles per box.
1. Convert units and area
Depending on your choice, all internal calculations are done in square feet:
- US mode: your area is already in ft².
- Metric mode: area in m² is converted to ft² using 1 m² ≈ 10.764 ft².
The tool also keeps a metric copy so it can show both ft² and m² in the results without asking you twice.
2. Area of one tile
In US mode, tile size is given in inches:
Tile area (ft²) = (length_in × width_in) ÷ 144
In metric mode, tile size is given in centimetres:
Tile area (m²) = (length_cm ÷ 100) × (width_cm ÷ 100)
then converted to ft² using the same 10.764 factor.
3. Tiles without and with waste
Once it knows area per tile, the calculator finds the theoretical tile count:
Tiles (no waste) = total area (ft²) ÷ tile area (ft²)
It then applies a waste factor based on pattern:
- Straight / grid: factor ≈ 1.10 (about 10% extra).
- Brick / offset: factor ≈ 1.12.
- Diagonal / herringbone: factor ≈ 1.15.
Tiles with waste = tiles (no waste) × waste factor
The tool then rounds up to a whole tile for the “tiles to order” figure.
4. Tiles per box and box counts
If you provide a tiles per box number, the calculator converts tiles into boxes:
Boxes (raw) = tiles with waste ÷ tiles per box
Boxes to order = ceil(Boxes (raw))
This is how you end up with a practical whole-box recommendation you can compare to quotes or supplier suggestions.
The formulas are kept deliberately transparent so you can follow the numbers, try different tile sizes or patterns and sanity-check everything with your tiler before you buy.
References and further reading on tile quantities
These resources expand on tile take-offs, waste and layout planning:
- B&Q — Tiling calculator
- HomeAdvisor — Tile calculator and project guide — practical advice on area, grout lines and typical waste allowance.
Use this calculator for quick planning, then lean on your tiler and supplier for final waste choices, box counts and layout details for your specific tile and room.