Tile Calculator (Rectangular)
Calculate how many tiles to buy for a rectangular area, including the allowance for cuts and waste. Enter the room and tile dimensions.
Tiles
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How to estimate tiles for a rectangular area
The formula is tiles = (width × length × (1 + loss%)) / tile_area. Tack on a 10% loss margin, or 15% if you're going diagonal or facing a lot of cuts. Then divide the total m² by the box yield, which usually lands between 1.5–2.5 m² per box depending on the format. One thing worth being strict about: buy from the same batch (lote/tonalidade), or you'll end up with color variation across the floor. And budget for the supporting materials too. Use AC-I mortar on indoor walls and floors, AC-II in wet areas, and AC-III for facades and pools, figuring on 4–5 kg/m²; grout (rejunte) runs about 0.5 kg/m². The PEI rating tells you how the tile handles abrasion: PEI 3 for residential rooms, PEI 4 for kitchens and entrances, PEI 5 for high-traffic or commercial spaces. On the technical side, NBR 13753 (laying) and NBR 13818 (ceramic tile specs) lay down the Brazilian rules.
Applications
Home renovations, redoing a bathroom or kitchen, tiling a facade, the laundry room, a balcony or service area, the deck around a pool, and commercial floors.
FAQ
Why 10% extra? It covers the cuts around corners and plumbing, the pieces that break while you're laying them, and a little reserve for repairs down the road. Going diagonal? Use 15%.
What PEI do I need? PEI 3 handles bedrooms and living rooms, PEI 4 suits kitchens and entrances, and PEI 5 is for stores and anywhere with heavy foot traffic. Bathroom walls don't carry a PEI rating at all, since nobody walks on them.
Porcelain or ceramic? Porcelain (porcelanato) absorbs less than 0.5% water and stands up to more, so it's the pick for facades and wet areas. Common ceramic is the cheaper option for indoor walls and floors that don't see much traffic.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.