How many square feet is a 20×20 room?
20 ft × 20 ft = 400 sq ft · 44.44 sq yd · 37.16 m² · perimeter 80 ft
The math is one line: length × width. Twenty by twenty is the classic two-car garage footprint — 400 square feet, which is also why it shows up constantly in great-room, studio and workshop plans: it is the largest square most residential spans handle comfortably.
Check it — or change it — in the calculator
The room is pre-loaded below. Adjust the numbers to your real measurements, add an alcove or subtract an island as another row, and the totals update as you type.
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| Cut-outs subtracted | — |
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| Area incl. waste | — |
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Everything is calculated locally in your browser — no measurements are sent anywhere. Mixed units are converted exactly (1 ft = 0.3048 m, 1 sq yd = 9 sq ft, 1 acre = 43,560 sq ft).
What is a 20×20 room usually used for?
- Two-car garage — two vehicles with a workbench wall (the size this footprint is famous for)
- Great room — living, dining and kitchen zones in one open 400 sq ft square
- Studio apartment shell — the whole home, minus bath, in a single room
- Workshop / maker space — machines on the perimeter, assembly table in the center
At the calculator's default price of $4.50 per sq ft with 10% waste, flooring this room costs about $1,980 in materials — change the price field to your product to get your own figure.
The same room in other units
| Unit | Area |
|---|---|
| Square feet | 400 sq ft |
| Square yards | 44.44 sq yd |
| Square meters | 37.16 m² |
| Square inches | 57,600 sq in |
| Acres | 0.0092 acres |
Other common room sizes
Questions about 20×20 rooms
Is a 20×20 room 400 sq ft including the closet?
The 400 sq ft is the full rectangle, walls to walls, so a closet inside that outline is already included. A closet outside the rectangle adds its own little rectangle on top — add it as a row in the calculator.
How much flooring do I need for a 20×20 room?
Order for 440 sq ft — the area plus 10% waste for cuts. For diagonal or herringbone layouts use 15%, i.e. about 460 sq ft. The flooring calculator turns that into boxes for your specific product.