Free Grout Calculator
Calculate how much grout you need based on tile size, grout joint width, and tile thickness. Get results in pounds of grout.
Typical: 1/16" to 1/2"
Standard tile is 3/8 inch
Grout Needed
7.8 lbs
Grout Needed vs Total Area
How to Calculate Grout Needed
Formula
Grout Volume = Area × Joint Width × Tile Thickness × (12/Tile Length + 12/Tile Width) × 12
This calculates the linear inches of grout joints per square foot, multiplied by the cross-section area (joint width × tile thickness). Grout powder weighs approximately 0.058 lbs per cubic inch when mixed. Results depend heavily on joint width — even small changes in joint size significantly affect the amount of grout needed.
Example Calculation
120 sq ft of 12×12 inch tile, 1/8 inch grout joint, 3/8 inch thick tile.
- 01Linear inches of joints per sq ft = (12/12 + 12/12) × 12 = 24 inches
- 02Joint cross-section = 0.125 × 0.375 = 0.047 sq in
- 03Grout volume per sq ft = 24 × 0.047 = 1.125 cu in/sq ft
- 04Total grout volume = 120 × 1.125 = 135 cu in
- 05Grout weight = 135 × 0.058 = 7.8 lbs
- 06Bags (25 lb) = 1 bag
Frequently Asked Questions
Learn More
How to Calculate Concrete Needed for Any Project
Learn how to calculate the exact amount of concrete needed for slabs, footings, columns, and other projects. Covers volume formulas, waste factors, and ordering tips.