Construction Tool
Room Area Calculator
Find the exact square footage of your room. Easily piece together complex L-shaped rooms or large spaces by defining a base square and adding or subtracting smaller zones like closets and kitchen islands.
Base Room Dimensions
Add Areas (Closets, Alcoves)
Subtract Areas (Islands, Fireplaces)
How to measure arbitrary rooms
Rooms are rarely perfectly square. Most contain closets, small alcoves, fireplaces, or fixed kitchen islands that you don't need flooring or painting on.
- The Base Rectangle: Find the longest contiguous length and width of the room. Use this as your Base Dimension.
- Additions: Measure the length and width of any extra spaces outside the main rectangle (like an entryway hall or walk-in closet). Click "Add Area" and input them.
- Deductions: Measure the width and depth of obstacles inside the base rectangle that you can't walk on or don't need materials for (like a kitchen island, stairs, or hearth). Click "Add Deduction" to subtract them from the total.
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