Home Improvement
Grout Calculator
Enter area, tile size, joint width and depth, plus coverage or bag size, to see kg and bags.
How much tile grout do I need?
Tile grout need depends on tiled area, how large the tiles are, and how wide and deep the joints are. Many bags publish a simple coverage rate in kilograms per square metre for a stated tile and joint size — enter that rate for the fastest estimate, add waste, and divide by bag weight. The tool also shows an approximate joint-volume formula using tile length and width plus joint width and depth with a typical grout density, useful when the bag chart does not match your format. Narrow joints on large tiles use far less than mosaic with wide joints. Confirm the product data sheet before ordering. Related setting materials are covered in the tile adhesive and tile calculator tools.
Worked example
12 m² at 1.2 kg/m² = 14.4 kg; +10% ≈ 15.8 kg. In 5 kg bags that is 4 bags. Compare with the joint formula if your tile size differs from the chart assumption.
Limits and assumptions
Coverage charts assume a stated joint size. Epoxy and cementitious grouts differ in density. Wall vs floor and porous tiles can change uptake.
Frequently asked questions
Which result should I trust — coverage or joint formula?
Prefer the manufacturer coverage for your exact tile and joint. Use the joint formula as a cross-check when charts are missing.
Do I grout the same day as tiling?
Follow the adhesive and grout instructions — open time and wash-off windows vary. Quantity maths is independent of timing.
Is waste necessary?
Yes — mixing leftovers, wash-off and colour-batch continuity usually justify 5–15% extra.
How do I convert kg/100 m² style charts?
Divide by 100 to get kg/m², then enter that as the coverage rate.