Tile Calculator

How the Tile Calculator works

The tile calculator estimates the number of tiles, number of boxes, adhesive quantity, and total material cost for any floor or wall project. Enter your room dimensions, tile size, grout joint width, and waste percentage to get an accurate purchase quantity — preventing both over-buying and the frustration of running short mid-project.

Tile quantity and box count

The calculator divides the net room area by the area of a single tile (including grout gap) to get the base tile count, then adds the waste percentage on top. Most tilers recommend 10% wastage for straight-lay patterns and 15% for diagonal or herringbone layouts where more cuts are made. The result is rounded up to whole tiles, then divided by your box size.

Waste percentage guidelines

A standard rectangular room with a grid layout needs 10% extra tiles to cover cuts at walls and breakages. Complex patterns like 45° diagonal, basket weave, or chevron typically require 15–20% extra. Mosaic tiles on curved surfaces may need up to 25% wastage. The tool's adjustable waste slider lets you match the right figure to your actual laying pattern.

Grout joint width and adhesive coverage

Grout joint widths range from 2 mm for polished porcelain to 10 mm for rustic stone or large-format tiles. Wider joints slightly reduce the effective tile count but increase grout consumption. Standard tile adhesive covers approximately 4–5 m² per 20 kg bag when applied with a 6 mm notched trowel, a figure used internally by the cost estimator.

India standard tile sizes

Popular floor tile sizes in India include 600×600 mm, 800×800 mm, and 1200×600 mm for large spaces, and 300×300 mm for bathrooms. Wall tiles are commonly 300×450 mm or 300×600 mm. The calculator accepts any custom tile dimension in millimetres or centimetres, making it equally useful for imported and locally manufactured tiles.

Frequently asked questions

How much tile wastage should I add?

Add 10% for simple rectangular rooms with straight tile layouts along the walls. Add 15% for diagonal layouts, rooms with many cuts, or irregular L-shaped and curved spaces. For large-format tiles (600 mm or larger), use 10–15% because each miscut wastes a larger area. Always round up to the nearest full box when ordering.

What grout joint width should I use?

For rectified (precision-cut) tiles: 2–3 mm joints. Standard floor tiles: 3–5 mm joints. Natural stone or handmade rustic tiles: 5–10 mm joints. Wider joints require more grout but help conceal slight irregularities in tile size and subfloor level. Always check the tile manufacturer's recommendation, as some thin-set systems require a minimum joint width.

How many tiles per m²?

For 600×600 mm tiles with 3 mm joints: tiles per m² = 1 / (0.603 × 0.603) ≈ 2.75 tiles per m². For 300×300 mm tiles with 3 mm joints: approximately 10.7 tiles per m². The calculator adjusts this automatically based on your chosen tile size and joint width, giving you the exact count plus any wastage you specify.