Room Size Calculator
Calculate room area and perimeter from length and width.
Planning estimate only. Check product specifications, site conditions and local codes before ordering or building.
How to calculate room size and area
Room area in square feet = length × width. Perimeter = 2 × (length + width). Square yards = square feet ÷ 9.
Planning notes
Use this room area calculator when you need to measure a room, estimate its floor area or work out the square feet of a room. Enter the finished inside length and width above. For L-shaped or irregular rooms, split the floor into rectangles, calculate each section and add the areas together. Once you know the room measurements, use the Carpet, Flooring or Wall Square Footage calculators for material planning.
- For L-shaped rooms, split the floor into rectangles and add their areas.
- Use finished inside dimensions for flooring and room-size estimates.
Related calculators
Use related tools for the next measurement or material quantity in your project.