Grout Calculator — Free Online Grout Calculator
Estimate how much grout your tile project needs. 100% free, no signup.
How much grout do I need?
Grout usage depends on tile size, tile thickness and grout-line width: bigger tiles and thinner lines use less grout, while small mosaics and wide lines use much more. This gives a physics-based estimate — always check the coverage chart on your grout bag, and buy a little extra.
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Frequently asked questions
Why does tile size change grout amount?
Grout fills the lines between tiles. Larger tiles have fewer lines per square foot, so they need much less grout than small mosaic or subway tiles.
Sanded or unsanded grout?
Use sanded grout for lines 1/8 inch and wider, and unsanded for thinner lines. Coverage per pound is similar; this estimate works for both.
Want to see the finished tile?
Download RoomGPT free and preview tile, grout color and full redesigns on a photo of your real room.