Room Layout Calculator
Check the clearances in a room and find the largest furniture footprint that still leaves comfortable walkways.
Last updated · View algorithm, constants and default inputs (JSON)
About this calculator
Comfortable circulation needs about 36 inches of clear floor between furniture and walls in a main path, and 18 inches to squeeze past. Planning the walkway first tells you how much space is actually left for seating. Usable area reserves the entered walkway width along every wall, so that clearance is subtracted from both room dimensions. Furniture dimensions are simplified planning estimates.
Worked example
calculated with the default values below
Room length 14 ft · Room width 12 ft · Desired walkway 36 in Floor area 168.0 sq ft · Usable area after walkways 48.0 sq ft · Max sofa length along long wall 8.0 ft · Max seat run along short wall 6.0 ft
General background references
Disclaimer
These calculators provide planning estimates only. Building codes, wiring regulations and safety requirements differ by country and change over time, and nothing here replaces a licensed professional or a permit. For structural, electrical or gas work, follow local code and have the installation inspected.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
g = k ÷ 12; U = max(0,(L - g)(W - g)); sofa = max(0,L - 2g)
- L
- Room length (ft)
- W
- Room width (ft)
- k
- Walkway clearance (in)
- g
- Walkway clearance (ft)
- U
- Usable furnished area (sq ft)
Usable area subtracts twice the clearance width from each room dimension. Furniture sizes are planning estimates.
Frequently asked questions
How is usable area calculated?
The entered walkway width is reserved along every wall, so the tool subtracts twice that width from both the room length and width before multiplying. This is a simplified layout estimate; doors, built-ins and furniture clearances are not modeled.