Square Footage Calculator
Calculate area, perimeter, and material needs for rooms and spaces.
Rooms/Areas
Material Calculations
Height of walls for paint calculations
Area one gallon of paint covers
Extra flooring for cuts and waste
Results
Unit Conversions
| Measurement | Imperial | Metric |
|---|---|---|
| Area | 180 ft² | 16.72 ft² |
| Flooring | 198 ft² | 18.39 ft² |
The area of a rectangular room is calculated using this formula:
Area = Length × WidthFor irregular shapes, break the area into rectangles and add them together.
When calculating paint needs:
- One gallon (3.78 liters) typically covers 350-400 square feet (32-37 m²) with one coat
- Subtract window and door areas for more accuracy
- Plan for two coats on new drywall or when changing colors dramatically
- Add extra for textured surfaces, which require more paint
- Consider primer for new surfaces or significant color changes
When calculating flooring materials:
- Add 5-10% extra for simple rectangular rooms
- Add 15-20% for complex layouts with many cuts
- For diagonal installations, add 15-20% extra
- For tile, factor in grout lines when calculating
- Buy all flooring from the same lot/batch to ensure color matching
How to Use This Square Footage Calculator
Our square footage calculator helps you measure spaces and estimate material needs for home improvement projects. Here's how to use it:
- Enter the length and width of each room or area.
- Add multiple rooms by clicking the Add Room button.
- Customize the wall height for paint calculations.
- Adjust paint coverage based on your paint type.
- Set the flooring waste factor percentage for your project.
- Switch between imperial (feet) and metric (meters) units as needed.
The calculator will instantly show the total area, perimeter, wall area, and material needs for your project.
Understanding Square Footage
Square footage (or square meters in metric) is the measurement of area within a space. It's calculated by multiplying the length by the width of a room or area.
For example, a room that is 10 feet long and 12 feet wide has a square footage of 120 square feet (10 × 12 = 120).
This measurement is essential for:
- Determining how much flooring material to purchase
- Calculating paint needed for walls
- Estimating project costs
- Comparing property sizes
- Planning furniture layouts
Material Estimation Guide
| Material | Coverage | Waste Factor | Tips |
|---|---|---|---|
| Interior Paint | 350-400 sq ft/gallon | 10% | One gallon typically covers a medium-sized room with one coat |
| Laminate Flooring | Per package specs | 10% | Add extra for simple rectangular rooms |
| Hardwood Flooring | Per package specs | 15% | Higher waste factor due to wood imperfections |
| Tile Flooring | Per box specs | 15-20% | Account for cuts, breakage, and pattern matching |
| Carpet | Roll width varies | 10-15% | Consider direction of carpet pile and room layout |
Note: These are general guidelines. Specific materials and project requirements may vary.
Measuring Irregular Spaces
For rooms with irregular shapes:
- Divide and conquer: Break the space into rectangles or squares.
- Measure each section: Calculate the area of each rectangle separately.
- Add the areas: Sum up all the individual areas for the total square footage.
For example, an L-shaped room can be divided into two rectangles. Calculate the area of each rectangle and add them together for the total square footage.
Example: L-shaped Room
Main section: 15 ft × 12 ft = 180 sq ft
Extension: 8 ft × 6 ft = 48 sq ft
Total area: 180 sq ft + 48 sq ft = 228 sq ft