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πŸ“ Square Footage Calculator

Instantly calculate the area (square footage) of any shape β€” rectangles, circles, triangles, trapezoids, sectors and more. Include optional price estimation.

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β–­ Rectangle

Length Width
ft
ft
$

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Square Footage Reference & Formulas

Unit conversions and area formulas for common shapes.

Unit Conversions

1 acre = 43,560 sq ft
1 sq yard = 9 sq ft
1 sq meter β‰ˆ 10.764 sq ft
1 sq inch = 1/144 sq ft

Rectangle

Area = Length Γ— Width

Multiply length by width to find the area. Multiply by quantity for multiple rooms.

Circle

Area = Ο€ Γ— (Diameter/2)Β²

Square the radius (half diameter) and multiply by Ο€ (β‰ˆ 3.14159).

Triangle (3 sides)

s = (a+b+c)/2
Area = √(s(s-a)(s-b)(s-c))

Uses Heron's formula to calculate area from three known side lengths.

Trapezoid

Area = (Base1 + Base2) / 2 Γ— Height

Average the two parallel bases and multiply by the height between them.

Sector (Pie Slice)

Area = Ο€ Γ— rΒ² Γ— (angle/360)

Fraction of a circle's area based on the central angle in degrees.

Common Uses for Square Footage Calculations

🏠 Flooring Installation

Calculate how much hardwood, laminate, tile or carpet you need. Add 5–10% extra for waste and cuts.

🎨 Painting a Room

One gallon of paint covers 200–400 sq ft. Calculate total wall area (subtract windows and doors) to estimate paint needed.

🌱 Landscaping & Lawn

Determine how much sod, seed, mulch or fertilizer you need based on the total lawn area in square feet.

πŸ—οΈ Construction & Renovation

Estimate material costs for decks, patios, driveways, and foundations using accurate square footage.