Square Footage Calculator
Area Estimate
Add rooms above to calculate total square footage.
Use our free Square Footage Calculator to quickly calculate the area of a room, floor, wall, yard section, or other rectangular space. Enter the length and width using feet and inches to estimate the total area in square feet.
This square foot calculator is designed for everyday U.S. home improvement and measurement needs. It can help homeowners, renters, contractors, and DIY users estimate floor area before planning flooring, paint, tile, carpet, or other projects.
What Is a Square Footage Calculator?
A square footage calculator is an online tool used to determine the area of a space measured in square feet.
For a rectangular area, square footage is calculated by multiplying the length by the width.
For example, a room measuring:
12 feet long × 10 feet wide
has an area of:
120 square feet
Using an sq foot calculator can save time when measuring multiple rooms or planning materials for a home improvement project.
Square footage is commonly used in the United States for measuring interior floor space, rooms, walls, patios, flooring projects, and other residential or commercial areas.
You can also explore our Home Improvement Calculators to estimate materials for painting, flooring, concrete, roofing, landscaping, and fencing projects.
How to Calculate Square Footage
If you want to know how to calculate square footage, use this basic formula:
Square Footage Formula
Square Feet = Length × Width
Both measurements should be expressed in feet.
Example
Length:
15 feet
Width:
12 feet
Calculation:
15 × 12 = 180 square feet
The total area is:
180 sq ft
How to Use the Square Footage Calculator
Using our square foot calculator takes only a few steps.
1. Measure the Length
Measure the longest side of the area.
For more information about the formulas, unit conversions, assumptions, and rounding used across My Panda Tools, review our Calculation Methodology.
Example:
14 feet 6 inches
2. Measure the Width
Measure the other side of the space.
Example:
11 feet 4 inches
3. Enter Your Measurements
Enter the length and width into the calculator.
If inches are included, the calculator can convert them into feet before calculating the area.
4. Calculate Square Feet
The calculator multiplies the converted length and width to estimate the total square footage.
How to Calculate Square Feet With Inches
Measurements are not always whole numbers.
For example:
12 feet 6 inches
To convert inches into feet:
6 ÷ 12 = 0.5 feet
Therefore:
12 feet 6 inches = 12.5 feet
If a room measures:
12 ft 6 in × 10 ft
Calculation:
12.5 × 10 = 125 square feet
A square footage calculator makes this conversion easier when your measurements include both feet and inches.
Worked Example
Suppose a bedroom measures:
Length: 13 feet 6 inches
Width: 11 feet
Convert 6 inches to feet:
6 ÷ 12 = 0.5
Length becomes:
13.5 feet
Now calculate:
13.5 × 11 = 148.5 square feet
Estimated room area:
148.5 sq ft
Square Footage Examples
| Length | Width | Square Footage |
|---|---|---|
| 10 ft | 10 ft | 100 sq ft |
| 12 ft | 10 ft | 120 sq ft |
| 12 ft | 12 ft | 144 sq ft |
| 15 ft | 12 ft | 180 sq ft |
| 20 ft | 15 ft | 300 sq ft |
| 25 ft | 20 ft | 500 sq ft |
These examples assume rectangular spaces.
How to Calculate Square Footage of a Room
To calculate square feet for a rectangular room:
- Measure the room’s length.
- Measure the room’s width.
- Convert inches to feet if necessary.
- Multiply length by width.
For example:
Bedroom: 14 ft × 12 ft
14 × 12 = 168 sq ft
Estimated room area:
168 square feet
How to Calculate Square Footage of Multiple Rooms
If you need the total area of several rooms, calculate each room separately and then add the results together.
Example:
Living Room:
15 × 12 = 180 sq ft
Bedroom:
12 × 10 = 120 sq ft
Office:
10 × 9 = 90 sq ft
Total
180 + 120 + 90 = 390 square feet
This approach is useful when estimating flooring or calculating the usable area of several spaces.
How to Measure an Irregular Shaped Room
Not every room is a perfect rectangle.
For an irregular space, divide the area into smaller rectangles or simple shapes.
For example:
Section A: 12 × 10 = 120 sq ft
Section B: 5 × 4 = 20 sq ft
Total:
120 + 20 = 140 sq ft
A basic sq foot calculator can be used for each section, and the individual areas can then be added together.
Square Feet vs. Square Yards
Square feet and square yards both measure area, but they are different units.
1 square yard = 9 square feet
To convert square feet to square yards:
Square Yards = Square Feet ÷ 9
Example:
450 sq ft ÷ 9 = 50 sq yd
This conversion can be useful when comparing flooring or carpet measurements.
Square Feet vs. Acres
For larger outdoor areas:
1 acre = 43,560 square feet
To convert square feet to acres:
Acres = Square Feet ÷ 43,560
Example:
21,780 sq ft ÷ 43,560 = 0.5 acre
Why Square Footage Matters for Home Projects
Accurate square footage is important when estimating materials for projects such as:
- Flooring
- Carpet
- Tile
- Paint
- Drywall
- Roofing
- Concrete
- Decking
- Landscaping
Knowing the area helps you estimate how much material may be required and compare project costs more effectively.
However, actual material quantities may need to include extra allowance for waste, cuts, overlaps, pattern matching, installation methods, or manufacturer recommendations.
Square Footage for Flooring Projects
For flooring, first calculate the total floor area.
Once you know the floor area, use our Flooring Calculator to estimate the amount of flooring material needed for your project.
Example:
Room: 16 ft × 12 ft
Area = 192 sq ft
Installers often purchase additional material to account for cutting and waste.
The exact waste allowance can depend on the material, room shape, installation pattern, and manufacturer guidance, so the square footage calculator should be used as a starting estimate rather than an exact purchasing quantity.
Square Footage for Paint Projects
Square footage can also help estimate wall area for paint projects.
If you are measuring walls or ceilings for a painting project, use our Paint Calculator to estimate paint coverage and the quantity of paint required.
For one rectangular wall:
Wall Area = Wall Width × Wall Height
Example:
12 ft × 8 ft = 96 sq ft
If calculating multiple walls, calculate each wall separately and add the areas together.
Doors, windows, multiple coats, and paint coverage rates may affect how much paint is actually required.
Core Assumptions
- Length and width measurements are accurate.
- Measurements are converted into compatible units before calculation.
- Rectangular-area calculations use length × width.
- Inches are converted using 12 inches = 1 foot.
- The calculator provides an area estimate in square feet.
- Irregular spaces should be divided into smaller measurable sections.
- Calculations use the dimensions entered by the user.
System Limitations
- Measurement errors can affect the result.
- Irregular shapes may require multiple calculations.
- The calculator does not automatically account for material waste.
- Doors, windows, cutouts, or obstacles may need to be handled separately.
- Construction plans may use different measurement standards.
- Material coverage varies by product and manufacturer.
- Results are estimates for informational and planning purposes.
- Important project measurements should be verified before ordering materials.
Frequently Asked Questions About Square Footage
Multiply the length of the space by its width. For example, a 12-foot by 10-foot room has 120 square feet.
The basic formula is:
Square Feet = Length × Width
Both measurements should be expressed in feet.
Convert the inches into feet by dividing them by 12, add that value to the feet measurement, and then multiply length by width.
A 10-foot by 10-foot room contains:
10 × 10 = 100 square feet
A 12-foot by 12-foot room contains:
144 square feet
Calculate each room separately using length × width, then add all room areas together.
Divide the irregular room into smaller rectangles or simple shapes. Calculate each area separately and add them together.
Yes. A square footage calculator can estimate the floor area before purchasing flooring, carpet, or tile. You may need additional material for cuts and waste.
There are 9 square feet in 1 square yard.
There are 43,560 square feet in one acre.
