Tile & Flooring Calculator — Boxes, Thinset & Grout
Enter the room size and tile dimensions to get tile counts, boxes, thinset and grout, plus an installed budget range.
Your numbers
Results
- Floor area
- 120 sq ft
- Tiles needed2.00 sq ft each, 12% waste
- 68 pcs
- Boxes (≈15 sq ft)
- 9 boxes
- Installed cost
- $1,428 – $2,016
- Thinset mortar1/2" x 1/2" notch
- 2 bags (50 lb)
- Grout
- 1 bags (25 lb)
- Backer board
- 8 sheets (3x5)
- Transition / trim
- 44 lin ft
Quantities are estimates for planning. Verify spans, spacing and local amendments before ordering.
How the math works
- Tile count = floor area ÷ tile face area, plus waste. Use 10% for straight lays and 15–20% for diagonal or herringbone patterns.
- Thinset coverage is about 85 sq ft per 50 lb bag with a 1/2" square-notch trowel — large-format tile uses more.
- Grout coverage varies with joint width; 25 lb covers roughly 120 sq ft of 1/8" joints on 12x24 tile.
Code & best practice
- Large-format tile (any side over 15") requires 80% mortar coverage and a floor flat to 1/8" in 10 ft.
- Wet areas need a bonded waterproof membrane over backer board (ANSI A118.10).
- Deflection must not exceed L/360 for ceramic and L/720 for natural stone.
Frequently asked questions
How many 12x24 tiles for a 12x10 room?
120 sq ft ÷ 2 sq ft per tile = 60 tiles, or about 68 tiles with 12% waste.
How much thinset do I need?
About one 50 lb bag per 85 sq ft with a 1/2" notch trowel; large-format tile can drop that to 60 sq ft.
How much does tile installation cost?
Typical installed cost is $10–$20 per sq ft depending on tile size, pattern and floor prep.