Square Footage Calculator (multi-shape + flooring)
Add up areas from up to 4 rectangles, triangles, and circles, then size the flooring order with waste + cost.
Result
General calculation reads
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How to use this calculator
- Enter the L × W of each rectangle in your floor plan (set unused to 0).
- Triangles: base × height ÷ 2 (the inputs do the divide-by-2 for you).
- Circles: enter diameter (the inputs square the radius for you).
- Box coverage: check the flooring label — laminate boxes are typically 20-25 ft².
- Waste %: 10% is the default for straight patterns; bump to 15-20% for diagonals.
About this calculator
Most rooms aren't a perfect rectangle. This calculator lets you combine up to four shapes — two rectangles, a triangle, and a circle — to model an L-shaped great room, a rectangular living room plus a triangular bay window, a round breakfast nook, or any combination. Once you have the total square footage, the flooring estimate sizes the order with a waste buffer (10% is standard; raise to 15-20% for diagonal patterns or rooms with many cuts) and computes the box count and total cost at your price per ft². Set any unused shape to 0 — they drop out of the sum automatically.
Frequently asked
Why subtract waste — isn't the room already measured?+
Why round boxes UP?+
What about closets / hallways?+
Are circles and triangles common in real rooms?+
How accurate does my measurement need to be?+
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