A tile calculator takes the guesswork out of ordering floor or wall tiles by computing exactly how many you need based on your room dimensions and tile size. It accounts for grout lines, waste from cuts and breakage, and converts your total into boxes — so you order the right amount and avoid costly mid-project shortages or excess.
Tile Estimator
Room Dimensions
Tile Size
Installation Settings
Pricing (optional)
Project Breakdown
How to Use the Tile Calculator
Ordering the wrong number of tiles is one of the most common and costly mistakes in a renovation project. Buy too few and your batch may not match when you reorder — dye lots vary between production runs. Buy too many and you waste money on materials you will never use. This tile calculator prevents both scenarios by estimating exactly how many tiles, how many boxes, and what the total cost will be, all while accounting for grout lines and installation waste.
Step 1: Enter Your Room Dimensions
Start by entering the length and width of the area you want to tile — whether it is a bathroom floor, kitchen backsplash, or hallway. Use the unit toggle to switch between imperial (feet) and metric (meters). The calculator computes the total square footage or square meterage automatically. For irregular rooms, calculate each rectangular section separately and add the tile counts together.
Step 2: Choose Your Tile Size
Select one of the common presets — 12×12, 12×24, 6×6, 18×18, or 24×24 inch tiles — or click Custom to enter any tile dimensions. When working in metric mode, the presets switch to centimeter equivalents (30×30, 30×60, etc.). The tile calculator uses the tile's nominal size in your chosen unit, so make sure you enter the same unit system as your room dimensions.
Step 3: Set Grout Width and Waste Percentage
Grout width affects how many tiles fit across a given area. A wider grout joint means each tile effectively covers slightly more area (because the grout joint extends out from the tile edge), so the calculator factors this in. The default of 3 mm works for most floor tiles; use 1–2 mm for mosaic tiles or 6 mm for larger stone tiles.
The waste percentage covers tiles cut at edges, around obstacles, and occasional breakage. Ten percent is the standard recommendation for simple, rectangular rooms laid in a straight pattern. Increase to 15% for diagonal (45-degree) patterns or complex layouts, and to 20% for natural stone or tiles with strong directional patterns that require careful alignment.
Step 4: Enter Tiles per Box
Check the tile box or the supplier's website for the tile count per box. Enter that number in the "Tiles per Box" field, and the calculator will tell you exactly how many boxes to purchase, always rounding up to the nearest full box. Buying in complete boxes ensures you have consistent tile thickness and finish across your project.
Step 5: Add Pricing for a Cost Estimate
Optionally enter the price per tile or the price per square foot (or per square meter in metric mode). The calculator uses whichever price you provide — or prioritizes price per tile when both are entered — and shows a total material cost estimate. This figure covers tile materials only; factor in grout, adhesive, and labor separately for your full project budget.
Frequently Asked Questions
Is this tile calculator free to use?
Yes, this tile calculator is completely free with no signup required, no ads-walls, and no limits. All calculations run entirely in your browser — your measurements stay on your device and are never sent to a server.
Is my data private when I use this tool?
Absolutely. Every calculation runs locally in your browser using client-side JavaScript. No room dimensions, tile sizes, or project details are ever transmitted to any server. Your information remains completely private on your device.
How do I calculate how many tiles I need for a room?
Enter the room's length and width, then choose your tile size or enter a custom size. The calculator computes the total area, divides by each tile's area, adds your chosen waste percentage, and rounds up to the nearest whole tile. Enter tiles per box to also see how many boxes to buy.
Why should I add a waste percentage when ordering tiles?
Waste accounts for tiles cut at edges, corners, and around obstacles, as well as breakage during installation and future repairs. For simple rectangular rooms with straight layouts, 10% waste is standard. For diagonal layouts, complex cuts, or large tiles, use 15–20% to avoid running short mid-project.
How does grout width affect the tile count?
Grout lines slightly reduce the effective coverage per tile, as each tile occupies a bit less floor space than its nominal size. Wider grout joints (3–6 mm) have a noticeable effect, especially with smaller tiles. This calculator factors grout width into the effective tile dimensions so your tile count is accurate.
What tile sizes does the calculator support?
The calculator includes common presets — 12×12, 12×24, 6×6, 18×18, and 24×24 inch tiles — as well as metric equivalents like 30×30 and 30×60 cm. You can also enter any custom tile dimensions. The unit toggle lets you switch seamlessly between imperial (inches/feet) and metric (cm/meters).
Can I calculate the cost of tiles with this tool?
Yes. Enter the price per tile or price per square foot, and the calculator instantly shows the estimated total material cost. The cost field is optional — leave it blank if you just need the tile count and boxes.
Should I buy extra tiles beyond the waste percentage?
It is always wise to buy a few extra tiles beyond your calculated waste percentage and keep them for future repairs. Tile dye lots vary between batches, so a replacement purchased years later may not match perfectly. Buying 1–2 boxes extra ensures you have matching tiles for any future touch-ups.