How many tiles, how much adhesive, how much grout? Enter the room size, pick a tile format and joint width. The calculator covers cement, flexible and deformable adhesives with automatic large-format correction.
12 inch tiles - how many do you need?
How many tiles, how much adhesive, how much grout? Enter the room size, pick a tile format and joint width. The calculator covers cement, flexible and deformable adhesives with automatic large-format correction.
Working with 12 inch tiles? Each one covers {value_sq} sq in of floor or wall. A typical 10x12 ft bathroom (120 sq ft) with 12x12 in tiles needs roughly {value_tiles} tiles before waste. Add 10% for straight layouts or 15% for diagonal and herringbone patterns. The calculator below factors in tile size, adhesive type, trowel notch, grout joint width and waste allowance - enter your room dimensions and read off a complete materials list for 12 inch format tiles.
Tile Calculator
Fill in the fields below
💡 Fill in all required fields to unlock the calculate button
Tile, adhesive and grout - one calculator for the entire job
A 10 x 12 ft bathroom with 12 x 12 in porcelain tiles, 1/8 in joints and 10% waste needs 132 tiles, 3 bags of thin-set mortar and 2 packs of grout. At $5/sq ft for tiles, $20/bag for adhesive and $15/pack for grout, the total material cost comes to $670. This calculator handles all three materials in one step - enter the room, pick the tile size, choose the adhesive type and read off a shopping list.
How to use the tile calculator - step by step
- Room length and width - measure the floor or wall area with a tape measure. Enter both dimensions in feet. For an L-shaped room, split it into two rectangles and run the calculator twice.
- Tile length and width - enter the size of one tile in inches. Common sizes: 12 x 12, 12 x 24, 18 x 18, 24 x 24. For mosaic sheets, enter the sheet dimensions.
- Tiles per box (optional) - check the carton label. The calculator rounds up to full boxes so you know exactly how many to buy.
- Grout joint width - rectified (precision-cut) tiles: 1/16 in. Standard ceramic: 1/8 in. Natural stone or rustic: 3/16-1/4 in.
- Waste allowance - 10% for a simple rectangle. 15% for diagonal layouts or rooms with many cuts. 20% for herringbone or chevron patterns.
- Trowel notch size - matches the tile size. Bigger tiles need deeper notches. Tiles over 24 in trigger automatic back-buttering (+20% adhesive).
- Adhesive type - thin-set mortar for most jobs. Modified thin-set for heated floors or outdoor installations. Ready-mix mastic for small wall areas.
- Prices (optional) - enter tile cost per sq ft, adhesive bag price and grout pack price for a total material estimate.
- Read results - tile count, adhesive bags, grout packs, and total cost.
Adhesive coverage by trowel notch size
The trowel notch determines how much adhesive ends up under each tile. Deeper notches leave more mortar, which means more bags per project. Large-format tiles (over 24 in on any side) require back-buttering - the calculator adds 20% automatically.
| Trowel notch | Thin-set (lb/sq ft) | Modified (lb/sq ft) | Ready-mix (lb/sq ft) | Best for |
|---|---|---|---|---|
| 3/16 in | 0.51 | 0.61 | 0.41 | 4-8 in tiles, mosaics |
| 1/4 in | 0.61 | 0.72 | 0.51 | 8-12 in tiles |
| 5/16 in | 0.72 | 0.82 | 0.61 | 12-16 in tiles |
| 3/8 in | 0.92 | 1.02 | 0.82 | 16-24 in tiles |
| 1/2 in | 1.13 | 1.23 | 0.92 | Over 24 in (large format) |
Values in lb per sq ft. Large-format tiles (over 24 in) get an extra 20% for back-buttering. Actual coverage varies with substrate flatness and tile porosity.
How much waste to plan for
| Layout pattern | Recommended waste % | Why |
|---|---|---|
| Straight grid | 10% | Fewest cuts, most offcuts reusable |
| Brick / running bond | 10-12% | Staggered rows create half-tile cuts at edges |
| Diagonal (45 degrees) | 15% | Every edge tile needs an angled cut |
| Herringbone / chevron | 15-20% | Complex angles, many small offcuts |
| Multi-size pattern | 15-20% | Mixed sizes mean leftover partial tiles |
| Room with many niches | 15-20% | Each corner and niche adds cuts |
Practical examples
Need: 53 tiles, 2 bags adhesive, 1 pack grout
Need: 76 tiles, 4 bags adhesive, 2 packs grout
Need: 144 tiles, 13 bags adhesive (large-format +20%), 2 packs grout
Need: 352 tiles, 1 bag adhesive, 2 packs grout
Need: 14 tiles, 1 bag adhesive, 1 pack grout. Cost: $192 tiles + $20 adhesive + $15 grout = $227
FAQ - Frequently asked questions
Related tools
Paint Calculator
Calculate gallons of paint for walls and ceilings with coverage rates for five paint types - See calculator
House Building Cost Calculator
Estimate total construction cost per square foot for traditional, prefab and timber-frame builds - See calculator
Paving Stone Calculator
Calculate paving stones, aggregate and sand for driveways, patios and walkways - See calculator
Plaster Calculator
Calculate plaster quantity and bags for cement, gypsum and acrylic finishes - See calculator
Calculator verified by the LiczGrupa.pl team
Content, formulas and results have been reviewed for accuracy and relevance by our team of specialists.
Reviewed by: Patryk Matyjasik