🧴Grout Calculator
Work out how many pounds of grout your tile job needs.
Your tile job
You'll need about
7.4 lb of grout
1 bag of 25 lb · 100 sq ft
bags
1
lb
7.4
sq ft
100
🛒 Shopping list
- Grout (25 lb bags)1 bags
- Grout sealer1 bottles
Small tiles have many more joints, so they need far more grout than big tiles for the same floor.
How it works
Grout per sq ft = (tile length + tile width) ÷ (length × width) × joint width × joint depth × 144 cubic inches, times about 0.06 lb per cubic inch, plus waste.
Worked example
100 sq ft of 12 × 12 in tile, ⅛ in joints, ⅜ in deep:
- 24 ÷ 144 × 0.125 × 0.375 × 144 = 1.125 cu in per sq ft
- × 100 sq ft × 0.06 = 6.75 lb, plus 10% = 7.4 lb → 1 bag
Questions people ask
It depends on tile size and joint. With 12 × 12 in tile and ⅛ in joints, often well over 200 sq ft.
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Last updated September 28, 2026. These results are friendly estimates to help you plan — always double-check before buying or making big decisions.