Loading page
About this tool
Calculates how many tiles and boxes a floor or wall needs, plus the grout and adhesive quantities, counting the grout joint in the tile module.
A tile calculator converts a room or wall measurement into the number of tiles, the number of sealed boxes, and the grout and adhesive to buy with them. It counts the grout joint as part of each tile's covering module — (tile width + joint) × (tile height + joint) — which is why it gives a slightly lower tile count than a calculator that divides by the bare tile size. Grout uses the manufacturers' formula ((A + B) ÷ (A × B)) × joint × thickness × 1.6 kg per m², and adhesive the standard 1.5 kg per m² for every millimetre of bed depth.
Open Tile Calculator on AltFTool — it loads instantly in your browser.
Enter the values you already know.
Fine-tune the options to match your scenario.
Read the result and use it in your planning or reporting.
The grout gap is part of the covering module, so the count matches what is actually laid.
Real manufacturer formulas, not a flat guess, driven by tile size, joint width and trowel notch.
Rounds to sealed boxes and tells you the true wastage and the spares you will be left holding.
About 33 tiles bare, or 37 with a 10% wastage allowance. With a 3 mm grout joint each tile covers 603 × 603 mm = 0.3636 m², so 12 ÷ 0.3636 = 33.0 tiles. At four tiles per box that is 10 boxes, which delivers 40 tiles and leaves 6 spare.
For 600 × 600 mm tiles that are 9 mm thick with a 3 mm joint, about 0.14 kg per m². The formula is ((A + B) ÷ (A × B)) × joint width × tile thickness × 1.6, with every dimension in millimetres and 1.6 g/cm³ as the density of cementitious grout. Smaller tiles need far more — 100 mm mosaics use roughly six times as much.
Thin-bed adhesive is consumed at about 1.5 kg per m² for each millimetre of bed depth, and the trowel sets the depth: a 6 mm notch leaves roughly a 3 mm bed (4.5 kg/m²) and a 10 mm notch about 5 mm (7.5 kg/m²). A 12 m² floor with a 10 mm notch therefore takes about 90 kg — five 20 kg bags.
Around 5% for a straight grid in a rectangular room, 10% as a general default, and 15% or more for a 45-degree diagonal or a herringbone layout where every perimeter cut leaves an unusable offcut. Rounding up to sealed boxes usually pushes the delivered wastage higher still, which is shown separately here.
Add the Tile Calculatorwidget to your blog or website — free, responsive, no signup. Just keep the “Widget by AltFTool” credit link visible.
<iframe src="https://www.altftool.com/embed/widget/tile-calculator"
title="Tile Calculator — free AltFTool widget"
width="100%" height="640" style="border:0;border-radius:12px;overflow:hidden"
loading="lazy" referrerpolicy="no-referrer-when-downgrade"></iframe>
<p style="font-size:12px;margin:4px 0 0">Widget by <a href="https://www.altftool.com/tools/all/tile-calculator?utm_source=embed&utm_medium=widget">AltFTool — free online tools</a></p>