Square Foot Calculator 4 Sides
Calculate the square footage of any 4-sided shape. Enter the side length to compute the area of a regular 4-sided polygon.
4-Sided Polygon Calculator
For a regular 4-sided shape (square), enter the side length. For irregular 4-sided shapes, use our quadrilateral calculator.
For rectangles: Length × Width.
For irregular 4-siders: use diagonals.
How to Calculate Square Footage of a 4-Sided Shape
A 4-sided shape (quadrilateral) can be a square, rectangle, rhombus, parallelogram, trapezoid, or an irregular polygon. The simplest case is a regular 4-sided shape — a square — where all sides and angles are equal.
Regular 4-Sided Shape Formula
Other 4-Sided Shapes
- Rectangle: Length × Width — Rectangle Calculator →
- Trapezoid: [(a + b) ÷ 2] × h — Trapezoid Calculator →
- Irregular quadrilateral: ½ × d₁ × d₂ × sin(θ) — Quadrilateral Calculator →
Example Calculation
A square patio has sides of 12 feet each.
12² = 144 square feet (13.38 sq m)
Frequently Asked Questions
How do I calculate the area of a 4-sided shape? +
For a regular 4-sided shape (square), use Area = side². For rectangles, use Length × Width. For irregular 4-sided shapes, use the diagonal method.
What if all 4 sides are different lengths? +
Use the quadrilateral calculator with diagonals, or the irregular shape calculator with coordinate points for the most accurate result.
Is a square a special rectangle? +
Yes! A square is a rectangle where all four sides are equal. Both have four 90° angles.