Tile Grout Quantity Calculator
Estimate tile grout kilograms and whole bags from tile dimensions, joint geometry, tiled area, grout density and allowance.
Your results
Calculation breakdown
- Grout mass
- area × joint width × depth × (1/tile length + 1/tile width) × density
Worked example
Twenty square metres of 600 × 300 mm tile with 3 × 8 mm joints uses about 4.22 kg after 10% allowance, requiring one 5 kg bag.
Assumptions
- Tiles form a regular rectangular grid.
- Entered mixed density and joint depth match the selected product system.
Sources
Rates effective 23 August 2026.
How this calculator works
Smaller tiles create more joint length per square metre, while wider and deeper joints consume more grout. The calculator uses a repeating rectangular grid approximation, converts joint volume to mass using the entered mixed density, adds allowance and reports whole package demand.
Frequently asked questions
Why is grout density an input?
Different cementitious, epoxy and specialty products have different mixed densities, so the current technical sheet is more reliable than a generic value.
Does this include movement joints?
No. Movement and perimeter joints may require a compatible sealant rather than grout and must follow the selected installation system.
Will textured tiles use more grout?
They can, especially if joints are overfilled or the face is difficult to clean, so choose an allowance suited to the product and installer.