Tile & Flooring Calculator
Calculate exactly how many tiles, boxes, and grout you need for your floor, wall, or backsplash project.
How to Calculate Tile
Measure the area you want to tile in square feet. Then divide by the area of one tile (in square feet) to find the number of tiles needed. Always add a waste factor — 10% is standard for straight layouts, 15% for diagonal patterns, and 20% for complex layouts with lots of cuts.
Common Tile Sizes
| Tile Size | Area per Tile | Best For |
|---|---|---|
| 12×12 in | 1.00 sq ft | Floors, walls (most popular) |
| 12×24 in | 2.00 sq ft | Modern floors, shower walls |
| 3×6 in | 0.125 sq ft | Subway tile backsplashes |
| 18×18 in | 2.25 sq ft | Large floors, open areas |
| 24×24 in | 4.00 sq ft | Large open floor plans |
Choosing the Right Waste Percentage
The waste factor accounts for cuts, breakage, and mistakes. A straight grid layout with few obstacles only needs 5–10%. Diagonal patterns or herringbone layouts need 15%. Rooms with lots of angles, curves, or doorways should use 20%. It's always better to have extra tiles than to run short — tiles from different production batches can vary slightly in color.
Grout and Thinset Estimates
Grout coverage depends on tile size, grout line width, and tile thickness. As a general rule, a 25-lb bag of grout covers about 100–200 sq ft for standard 12×12 tiles with 1/8-inch grout lines. Thinset mortar coverage is approximately 60–70 sq ft per 50-lb bag when applied with a 1/4-inch notched trowel.
Tips for Your Tile Project
- Always dry-lay tiles before applying adhesive to check the layout and plan your cuts.
- Start from the center of the room and work outward for the most balanced look.
- Use tile spacers for perfectly even grout lines — remove them before grouting.
- Wait 24 hours after setting tiles before applying grout to allow thinset to cure.
- Seal grout after it dries (48–72 hours) to prevent staining and moisture absorption.
- Buy all your tile at once from the same lot number to ensure consistent color matching.
Frequently Asked Questions
A 10x10 foot room is 100 square feet. Add 10% for waste and cuts, so you need tile to cover 110 square feet. Using standard 12x12-inch tiles (1 sq ft each), that is 110 tiles. At 10 tiles per box, buy 11 boxes. For diagonal layouts, add 15% waste instead, bringing the total to about 115 tiles.
Plan for 10% extra tile for standard straight-lay patterns, 15% for diagonal or herringbone patterns, and 20% for complex layouts with many cuts and angles. Buy all your tile at once from the same production lot, as colors can vary slightly between batches. Keep leftover tiles for future repairs.
Tile materials cost $1-$5 per sq ft for ceramic, $3-$10 for porcelain, and $5-$15 for natural stone. Add $2-$3 per sq ft for thinset, grout, and supplies. Professional installation runs $5-$15 per sq ft for labor. A DIY 100 sq ft bathroom floor typically costs $200-$500 in materials using mid-range porcelain tile.
Larger tiles (12x24 or 18x18 inches) make small rooms appear more spacious because there are fewer grout lines breaking up the visual field. Light-colored tiles and thin grout lines enhance this effect. Conversely, small mosaic tiles can make a room feel busier and smaller. For small bathrooms, 12x24-inch tiles laid lengthwise are a popular choice.
A 25-lb bag of grout covers approximately 100-200 square feet for standard 12x12-inch tiles with 1/8-inch grout lines. Smaller tiles with wider grout lines need more grout — the same bag might only cover 50-75 sq ft for 4x4-inch tiles. Unsanded grout is used for joints 1/8 inch or narrower, while sanded grout is used for wider joints.