Square footage of an irregular room — split it into simple shapes and add the areas
You never measure an odd shape directly. Split the room into simple shapes the calculator knows — rectangle, triangle, circle, trapezoid — find each area, and add them. Here an L-shape is 12 × 8 (96 ft²) plus 7 × 6 (42 ft²) = 138 ft².
What this diagram shows
A plan view of an L-shaped room broken into two rectangles to find its area. Rectangle A is the full-width top section, 12 feet by 8 feet, which is 96 square feet. Rectangle B is the smaller bottom-left section, 7 feet by 6 feet, which is 42 square feet. A dashed line marks the split between them. Added together, 96 plus 42 gives a total of 138 square feet. The method generalizes: a bay or angled wall becomes a triangle (one-half base times height) or a trapezoid, and a rounded area becomes a circle (pi times radius squared) — you split the space into simple shapes, solve each, and sum them.
Square Footage Calculator
Free square footage calculator: add multiple rooms or odd shapes, subtract doors and windows, and convert to sq ft, sq yards, square meters and squares.
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