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HomeFAQCalculating Square Footage FAQWhat is the sq ft of a 20x20 room?

What is the sq ft of a 20x20 room?

A 20x20 room is 400 square feet. The math is simple: 20 feet x 20 feet = 400 sq ft. That's a large room by residential standards, roughly the size of a two-car garage, which is typically 20x20 or 20x22.

For context, 400 sq ft can comfortably hold a full living room arrangement with multiple seating areas, or serve as a spacious primary bedroom with a sitting area. If you're pricing flooring for a 400 sq ft space, budget for 420-440 sq ft of material to cover cuts and waste.

How many boxes of flooring for a 20x20 room?

Pick a material and layout to see how many boxes to buy, waste included. Box coverage varies by brand, so adjust the sq ft per box to match the label on yours.

19 boxes covers 400 sq ft plus 8% waste (432 sq ft of material at 23.6 sq ft per box).

Need a cost estimate too? Use the full flooring calculator.

As with any room, the stated dimensions assume a perfect rectangle. Real rooms have closets, bump-outs, and angled corners that change the true area. When you need the exact number rather than the nominal one, tracing the actual room outline on a floor plan gives you the precise area. MeasureFloorPlan calculates this automatically for any room shape once you've set the drawing's scale, which matters when you're ordering materials or verifying a listing's square footage claim.

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