About this calculator
Tiles for a floor, wall, shower or backsplash, with the thinset and grout to fix them, in one takeoff.
How it’s calculated
Each tile plus its joint covers (width + joint) × (length + joint). Tiles = area ÷ that × (1 + waste). Thinset coverage per 50 lb bag is about 90 sq ft with a ¼" square notch, and about 45 sq ft with a ½" notch for large tiles.
Worked example
With these inputs:
- Measure by
- Length × width
- Length
- 15 ft
- Width
- 12 ft
- Tile width
- 12 in
- Tile length
- 24 in
- Grout joint
- 0.125 in
- Layout
- Straight, many cuts (10%)
- Tiles per box (optional)
- 0
the result is:
- Tiles needed
- 98 tiles
- Area
- 180 sq ft
- Tiles per sq ft
- 0.49
- Grout (approx.)
- 10 lb
Tips from the trade
- Large-format tiles (longer than 15" or 380 mm) and anything laid diagonally need more waste and more adhesive.
- Lay out a dry row before mixing anything, and avoid slivers under half a tile at the edges.
- Back-butter large tiles for full coverage, especially in showers.
Common questions
How many tiles do I need for 100 sq ft?
12×24 tiles with ⅛" joints: about 50 tiles before waste, about 55 with 10%.
Results are estimates for planning and pricing. Check quantities against your drawings, the manufacturer’s data and local building codes before ordering.