Square Footage Calculator
Calculate the square footage of a rectangular area. Convert between square feet, yards, and meters. Estimate total cost based on price per square foot.
Square Feet is simply Length multiplied by Width, so a given percentage increase to either dimension raises the area by that same percentage -- there's no asymmetry between the two the way there can be with a fixed-reference calculation. Square Yards and Square Meters are that same figure re-expressed with fixed conversion factors (dividing by 9, or multiplying by 0.092903), so they move in lockstep with Square Feet rather than being independent calculations. Perimeter, by contrast, is twice the sum of Length and Width rather than their product, and because the calculator's default Length (20 ft) is larger than its default Width (15 ft), a proportional change to Length moves Perimeter more than the same proportional change to Width does at those defaults -- narrow that gap between the two dimensions and their effect on Perimeter converges. Total Cost only appears once you set Price per sq ft above its 0 default; it is Square Feet multiplied by that rate. This calculator assumes a simple rectangle -- it doesn't account for L-shapes, alcoves, or the extra area added by rounded or angled walls.
Inputs
Results
Square Feet
300 sq ft
≈ 7 king-size beds
How to Use This Calculator
- Enter the length and width of the rectangular area in feet.
- Optionally enter a price per square foot to calculate a total cost estimate.
- Read the area in square feet, square yards, and square meters for any unit you need.
- Use the perimeter output to estimate baseboard, fencing, or edging lengths.
How the result changes with Length
| Length | Square Feet |
|---|---|
| 1,000 | 15,000 sq ft |
| 3,500 | 52,500 sq ft |
| 6,500 | 97,500 sq ft |
| 9,000 | 135,000 sq ft |
What each input means
- Length
- Length of the shape or side.
- Width
- Width of the shape or side.
- Price per sq ft
- Optional: estimate total cost.
How this is calculated
Worked example, using the default values
- Identify Input ParametersLength = 20, Width = 15, Price per sq ft = 0 = 3 input(s) provided
- Calculate Square Feet300 = 300
- Calculate Square Yards33.33 = 33.33
- Calculate Square Meters27.87 = 27.87
Engine last updated . Checked against 1 independently-derived test — how we verify calculators.
Frequently Asked Questions
Do length and width affect the square footage equally?
Yes -- Square Feet is Length multiplied by Width, so a given percentage change to either dimension changes the resulting area by that same percentage regardless of which one you adjust. There's no built-in asymmetry between the two dimensions in this calculation.
Why does changing length move the perimeter more than changing width?
Perimeter is twice the sum of Length and Width, and at the calculator's default values Length (20 ft) is larger than Width (15 ft) -- so a given percentage increase to the larger dimension, Length, adds more actual feet to the total than the same percentage increase to the smaller dimension, Width.
How do square yards and square meters relate to square feet?
Both are the same Square Feet figure converted with a fixed factor: Square Yards divides by 9 (since a square yard is 9 square feet), and Square Meters multiplies by 0.092903. Neither is calculated independently from Length and Width -- they're derived directly from the Square Feet result.
Why is Total Cost zero if I don't enter a price?
Total Cost is Square Feet multiplied by Price per sq ft, and that price field defaults to $0 since it's an optional estimate. Enter your material or labor rate per square foot in the advanced Price per sq ft field to see a nonzero cost estimate.
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