A 20x20 cm tile covers 0.04 m², so you need exactly 25 tiles per square metre. A 12 m² room takes 300 tiles, or 330 with 10% waste.
20x20 Tile Calculator
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About 20x20 Tile Calculator
A 20 by 20 centimetre tile covers 0.04 square metres, so there are exactly 25 tiles to the square metre, which makes this the easiest size to estimate in your head. A 4 by 3 metre room of 12 square metres needs 300 tiles before waste and 330 with a 10 percent allowance. This page opens with the size already set to 20 by 20, so you only enter the room. Twenty centimetre squares are the format of patterned cement tiles, encaustic designs and terracotta, where the pattern is the point and a larger tile would lose it. They are also the practical choice for a shower floor that falls to a drain: a floor sloped in two directions cannot be covered by large rigid tiles without lipping, whereas small tiles follow the fall. The extra grout lines add grip underfoot, which matters on a wet floor or a terrace. The cost is labour, since laying 25 tiles per square metre takes far longer than laying three, and more grout to clean afterwards. Patterned tiles also need a dry layout before fixing so the design runs correctly across the room. For a larger square format see 30x30 Tile Calculator or 60x60 Tile Calculator.
How to use 20x20 Tile Calculator
Choose metric or imperial, then enter the floor, wall or shower dimensions
Enter tile length and width in centimetres or inches
See tile count and optional box count in metric and imperial
Frequently Asked Questions
How many 20x20 tiles per square metre?
Exactly 25, since each tile covers 0.04 square metres. Multiply your floor area by 25 for the raw count, then add the waste allowance on top.
How many 20x20 tiles for a 10 square metre room?
About 250 before waste and 275 with a 10 percent allowance. Patterned tiles laid to a design often need a little more, because some cuts have to come from a specific part of the pattern.
Are 20x20 tiles good for a shower floor?
Yes. A shower floor falls towards the drain, often in two directions, and small tiles follow that slope where a large tile would rock or leave raised corners. The extra grout lines also improve grip.
Do small tiles take longer to lay?
Considerably. At 25 tiles per square metre against fewer than 3 for a 60x60 tile, the laying and grouting time per square metre is much higher, which is worth allowing for in labour quotes.
Should I dry lay patterned 20x20 tiles first?
Yes. Lay out a section without adhesive to check how the pattern runs and where the cuts fall, especially with encaustic or cement tiles where each tile can differ slightly.