Tile Calculator
Room Dimensions
Tile Size
Select a common size or enter custom dimensions
Cost (Optional)
How Tile Calculation Works
Calculating tile quantity involves measuring your space, accounting for tile size, and adding extra for waste and cuts. Understanding grout requirements ensures you have enough materials for a complete installation.
1. Area Measurement
Multiply room length by width to get total square footage. For walls, measure height times width. For complex spaces, break into rectangles and add them together.
2. Grout Gap Spacing
Standard grout gaps are 1/8 inch for floor tiles and 1/16 inch for wall tiles. Larger tiles can use 1/4 inch gaps. Grout gaps don't affect tile count but impact grout quantity needed.
3. Waste Factor
Always add 10-15% extra tiles for cuts, breakage, and future repairs. Diagonal layouts need 15-20% waste. Complex patterns with many cuts require more waste allowance.
4. Grout Estimation
Grout needs depend on tile size, gap width, and tile thickness. Smaller tiles with more grout lines require more grout per square foot. Standard formula accounts for tile perimeter and gap dimensions.
Common Tile Sizes
Understanding standard tile sizes helps plan your project and estimate costs.
| Tile Size | Common Use | Tiles per Sq Ft | Typical Grout Gap |
|---|---|---|---|
| 12x12 inches | Standard floor tile | 1 tile | 1/8 inch |
| 12x24 inches | Rectangular floor tile | 0.5 tiles | 1/8 inch |
| 18x18 inches | Large floor tile | 0.44 tiles | 1/8 - 1/4 inch |
| 24x24 inches | Large format floor | 0.25 tiles | 1/4 inch |
| 6x6 inches | Small wall tile | 4 tiles | 1/8 inch |
| 3x6 inches | Subway tile | 8 tiles | 1/16 - 1/8 inch |
| 4x12 inches | Wall / backsplash | 3 tiles | 1/8 inch |
Worked Examples
Example 1: Kitchen Floor (Standard Layout)
Scenario: 12 ft x 10 ft kitchen floor with 12x12 inch tiles, straight layout
Calculation:
Tiles needed (no waste) = 120 tiles (1 per sq ft)
Waste factor (10%) = 120 × 0.10 = 12 tiles
Total tiles = 120 + 12 = 132 tiles
Grout needed = 120 sq ft × 0.45 lbs/sq ft ≈ 54 lbs
Example 2: Bathroom Wall (Subway Tile)
Scenario: 8 ft x 4 ft wall with 3x6 inch subway tiles, 1/8 inch grout gaps
Calculation:
Tiles per sq ft = 144 sq in / (3 × 6) = 8 tiles
Tiles needed (no waste) = 32 × 8 = 256 tiles
Waste factor (15%) = 256 × 0.15 = 38 tiles
Total tiles = 256 + 38 = 294 tiles
Grout needed = 32 sq ft × 0.8 lbs/sq ft ≈ 26 lbs
Example 3: Large Format Floor (Diagonal)
Scenario: 15 ft x 12 ft room with 24x24 inch tiles, diagonal layout
Calculation:
Tiles per sq ft = 144 sq in / (24 × 24) = 0.25 tiles
Tiles needed (no waste) = 180 × 0.25 = 45 tiles
Waste factor (20% for diagonal) = 45 × 0.20 = 9 tiles
Total tiles = 45 + 9 = 54 tiles
Grout needed = 180 sq ft × 0.25 lbs/sq ft ≈ 45 lbs
Privacy and Limitations
This tile calculator provides estimates for planning purposes. Actual tile and grout requirements may vary based on:
- Room shape complexity and number of corners or angles
- Tile layout pattern (straight, diagonal, herringbone, etc.)
- Tile thickness and grout type (sanded vs. unsanded)
- Installer skill level and cutting precision
- Manufacturer variations in tile sizing
Always consult with a professional installer and purchase 5-10 extra tiles beyond calculated amounts for future repairs. All calculations are performed locally in your browser - no data is stored or transmitted.
Related Tools
- Pixel Density Visualizer -- Calculate PPI from screen size and resolution
- Heat Index Calculator -- Calculate feels-like temperature from air temperature and humidity
- Concrete Stair Calculator -- Calculate concrete volume, step dimensions, and building code compliance for
- Public Speaking Timer -- Practice speech timing with visual warning cues and pacing checkpoints
Related Tools
View all toolsSquare Footage Calculator
Calculate area in square feet from room dimensions for flooring, painting, and more
Tip Calculator
Calculate tip amount, total, and per-person split
Online Compass
Digital compass using your device's magnetometer sensor
Split Bill Calculator
Split a total evenly across a group
Receipt Total Calculator
Add line items, tax, discounts, tip, and split totals instantly
Shopping List Builder
Build a smart shopping list with quantities, categories, and budget tracking
Tile Calculator FAQ
How do I calculate how many tiles I need?
Measure your room length and width to get the area in square feet. Calculate how many tiles fit per square foot based on tile size. Add 10-15% extra for waste and cuts. For example, a 100 sq ft room with 12x12 tiles needs 100 tiles, plus 10 extra (10% waste) = 110 tiles total.
What is the standard waste factor for tile installation?
The standard waste factor is 10% for straight layouts and simple rooms. Add 15-20% for diagonal layouts, complex patterns, or rooms with many corners and angles. This accounts for cuts, breakage, and future repairs.
How much grout do I need for my tile project?
Grout quantity depends on tile size, grout gap width, and tile thickness. For standard 12x12 tiles with 1/8 inch grout lines, you need approximately 0.4-0.5 lbs of grout per square foot. Smaller tiles with more grout lines require more grout per square foot.
What are the most common tile sizes?
Common floor tile sizes include 12x12, 12x24, 18x18, and 24x24 inches. Popular wall and backsplash tiles are 3x6 (subway tile), 4x12, and 6x6 inches. Large format tiles (24x24 and up) are increasingly popular for modern designs.
How do I calculate tiles per box?
Check the tile manufacturer's box label for coverage area or pieces per box. Most 12x12 tiles come 12-15 per box covering 12-15 sq ft. Larger tiles have fewer per box. Divide your total tiles needed by tiles per box to determine boxes required.
Should I include the grout gap in tile calculations?
No, calculate tiles based on tile size alone, not including grout gaps. The grout fills between tiles and doesn't affect the number of tiles needed. However, grout gap width is essential for calculating grout quantity.