About the Grout Calculator
Grout needed for a tiled area from tile size, joint width and tile thickness.
Also known as: grout quantity, how much grout, tile grout calculator, grout coverage.
How to use this calculator
- Enter area to grout, tile length, tile width, joint width and the other fields.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
kg/m² = (L + W) ÷ (L × W) × joint × thickness × 1.6
Worked example
Using the values pre-filled in the calculator above:
- Area to grout = 12 m²
- Tile length = 600 mm
- Tile width = 600 mm
- Joint width = 3 mm
- Tile thickness = 9 mm
- Waste allowance = 15 %
the calculator returns:
- Grout required: 1.99 kg
- Per square metre: 0.144 kg/m²
- 5 kg bags: 1
- 2.5 kg bags: 1