Tile Calculator Online Free Tool
Tile Calculator
Tile Calculator
Tile Size
Area to Cover
Gap Size (Grout Spacing)
Use positive values for gaps (grout spacing) or negative values for overlaps (roofing tiles)
Different patterns require different wastage factors
Optional: Box Size & Pricing
Tiles Needed
Base requirement (no wastage)
With Wastage
Including 10% wastage
Boxes Needed
@ 12 tiles per box
Calculation Details
Tile Area
0.00 cm² (0.0000 m²)
Total Area to Cover
0.00 m² (0.00 sq ft)
Coverage Efficiency
0.00%
Effective Tile Size (with gap)
12.25 × 12.25 cm
Wastage Amount
0 tiles
Layout Pattern
grid
Area Breakdown (m²)
The tile calculator determines how many tiles you need for a floor, wall, or backsplash. Enter the room dimensions and tile size to get the total tiles required, including the recommended overage percentage for cuts, breakage, and future repairs. Ordering the right amount up front is critical because tile colors vary between production lots, and a mismatch is noticeable in a finished installation.
Tile Quantity Calculation
Divide the total area to be tiled by the area of a single tile to get the base tile count. Always add an overage percentage to account for cuts at walls and corners, breakage during installation, and tiles to keep on hand for future repairs. The overage percentage increases with diagonal layouts, irregular room shapes, and intricate patterns.
Area to Tile (sq ft) = Room Length × Width (measure walls separately for wall tile) Tile Area (sq ft) = Tile Length (in) × Tile Width (in) / 144 Base Tiles = Area to Tile / Tile Area With overage: Floors (straight lay): +10% Floors (diagonal lay): +15% Walls: +10% Herringbone or complex patterns: +15-20% Final Order = Base Tiles × (1 + Overage %)
Always buy extra tiles from the same dye lot for future repairs. Colors vary between production runs.
Common Tile Sizes and Coverage
Tile sizes have shifted toward larger formats over the past decade. Large-format tiles (12×24 or bigger) create a cleaner, more modern look with fewer grout lines. They require a very flat, level subfloor — any variation over 1/8 inch in 10 feet will cause lippage (one tile edge higher than another). Small mosaic tiles and subway tiles work well for walls and backsplashes where large formats are impractical.
| Tile Size | Coverage per Tile | Common Application |
|---|---|---|
| 3×6 inch (subway) | 0.125 sq ft | Kitchen backsplash, bathroom walls |
| 4×4 inch | 0.111 sq ft | Bathroom walls, vintage look |
| 12×12 inch | 1.00 sq ft | Floors and walls, versatile |
| 12×24 inch | 2.00 sq ft | Bathroom floors, modern look |
| 16×16 inch | 1.78 sq ft | Kitchen and living room floors |
| 18×18 inch | 2.25 sq ft | Larger spaces, fewer grout lines |
| 24×24 inch | 4.00 sq ft | Large open areas, commercial |
| Mosaic (1×1 or 2×2) | Varies (sold by sheet) | Shower floors, decorative accents |
Layout Patterns and Their Impact on Waste
The installation pattern significantly affects both the final appearance and the amount of material wasted. Straight-stack layout (tile edges aligned both ways) minimizes waste and is easiest to install. Offset/brick pattern (half-tile stagger) is slightly more complex but hides grout lines well. Diagonal layout (45 degrees) creates a classic look but wastes 15% more tile due to angled perimeter cuts. Herringbone requires the most cuts and skill.
| Pattern | Extra Waste | Skill Level | Notes |
|---|---|---|---|
| Straight stack | 10% | Beginner | Easiest, least waste |
| Offset / brick | 10% | Beginner | Hides subfloor imperfections |
| Diagonal (45°) | 15% | Intermediate | Classic look, more cutting |
| Herringbone | 15-20% | Intermediate | Striking, high complexity |
| Basketweave | 15% | Intermediate | Traditional, mosaic look |
| Custom/mixed | 20%+ | Advanced | Plan carefully, consult a pro |
Subfloor and Surface Preparation
Tile installation fails most often due to inadequate subfloor preparation, not tile quality. Floors must be structurally sound, level within 1/8 inch over 10 feet (or 1/4 inch for large-format tiles), and free from flex. Ceramic and porcelain tile over a wood subfloor requires cement board or uncoupling membrane underlayment to prevent cracking from subfloor movement. Bathroom shower floors need a properly sloped mortar bed and waterproof membrane before tiling.
Frequently Asked Questions
How much extra tile should I buy?⌄
Buy at least 10% extra for a straight-lay floor installation in a rectangular room. Increase to 15% for diagonal installation or rooms with multiple cutouts (toilets, islands, hearths). Add 15-20% for complex patterns like herringbone or rooms with many corners. Buy enough from the same batch to complete the job with some left over: tile colors vary between production runs (dye lots), and a replacement tile from a different lot may be visibly different from the installed tiles.
Should I tile under cabinets?⌄
Best practice is to tile the entire floor including under cabinets. This allows future cabinet reconfiguration or replacement without exposing bare or patched subfloor. Tile under the cabinet toe kick area also provides a moisture barrier. The downside is extra material cost and time. If you are certain the kitchen layout will never change and budget is tight, tiling to the cabinet kick plates (not under) is acceptable for most kitchens.
How do I calculate tiles for a diagonal installation?⌄
Calculate the room area as normal (length × width in sq ft), divide by tile area (tile size in sq inches ÷ 144) to get base tile count, then multiply by 1.15 to add 15% for diagonal waste. The 15% accounts for the additional angled cuts required at all four walls. Diagonal tile at the perimeter creates triangular waste pieces that cannot be used elsewhere. This installation also requires more precise layout work: start from the center of the room and work outward in each direction.
What size tile should I use for a small bathroom?⌄
Large-format tiles (12×24 or larger) with minimal grout lines make a small bathroom feel more spacious and modern because the eye sees fewer lines. However, large floor tiles in a small bathroom shower require precision cutting around fixtures and may not work with a standard shower floor slope. A practical compromise for small bathrooms: 12×12 or 12×24 on the floor, 3×6 subway or 4×12 rectangular tile on the walls. This creates a classic, timeless look that photographs well and scales appropriately.
What is the difference between ceramic and porcelain tile?⌄
Porcelain tile is a type of ceramic tile fired at higher temperatures with finer clay, making it denser, less porous, and harder. Porcelain's water absorption rate is below 0.5%, making it suitable for any indoor or outdoor application including wet areas. Standard ceramic tile absorbs more water (1-6%), making it suitable for interior walls and low-traffic floors but not outdoor use or wet shower floors. Porcelain is also harder to cut and typically costs 25-50% more than standard ceramic. For floors, porcelain is almost always the better choice.