Grout Calculator

Q1. How much grout do I need?

Grout quantity depends on your tile size, the grout joint width, and the tile thickness, plus the total area. Smaller tiles and wider joints use more grout; large-format tiles with thin joints use less. The general approach multiplies tile area by joint width and depth to estimate volume, which is why a calculator helps. Grout is sold by the bag with manufacturer coverage charts. Our Grout Calculator estimates how many pounds or bags you need from your tile and joint dimensions.

Q2. What’s the difference between sanded and unsanded grout?

Sanded grout contains fine sand and is used for joints 1/8 inch and wider, where the sand adds strength and resists cracking and shrinkage. Unsanded grout is smoother and used for narrow joints under 1/8 inch and for delicate or easily scratched tiles like polished stone and glass, where sand could scratch the surface. Using the wrong type—sanded in too-narrow a joint or unsanded in too-wide a joint—leads to cracking or poor filling, so match grout to joint width.

Q3. Should I use cementitious or epoxy grout?

Cementitious grout is the traditional, easier-to-work, and more affordable choice for most walls and floors; it benefits from sealing to resist stains and moisture. Epoxy grout is made of resin and hardener—it’s highly stain-resistant, waterproof, and durable, making it excellent for showers, backsplashes, countertops, and high-moisture or heavy-use areas, and it generally doesn’t need sealing. Epoxy is harder to install and sets faster, so it’s less forgiving for beginners. Choose epoxy for performance in wet or stain-prone spots, cementitious for easier general use.

Q4. What grout joint width should I use?

Joint width depends on the tile: 1/16 inch suits rectified tiles and a tight modern look; 1/8 inch is the common all-purpose width for wall and floor tile; and 3/16 to 1/4 inch fits larger tiles, natural stone, and tiles with size variation. Wider joints use more grout and generally need sanded grout, while very thin joints use unsanded grout. Confirm your spacer size first, since the joint width directly drives how much grout you’ll use.

Q5. Do I need to seal my grout?

Cementitious grout is porous and should be sealed after it fully cures (often about a week) to resist stains, moisture, and mildew—especially on floors, showers, and backsplashes. A penetrating sealer is reapplied periodically over the years as it wears. Epoxy grout is naturally non-porous and stain-resistant, so it typically doesn’t require sealing. Sealing too soon traps moisture and weakens the grout, so always follow the grout manufacturer’s cure-time guidance before applying any sealer.