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Room Perimeter Calculator
Room Perimeter Calculator
Calculate the perimeter of rectangular or circular rooms for baseboards, trim, and fencing estimates.
ft
ft
Each door subtracts ~3 ft of baseboard.
Results appear as you type.
How to use
- Choose rectangle or circle.
- Enter dimensions in feet.
- Optionally subtract doorway gaps for baseboard runs.
Formula
rectangle: P = 2 × (L + W) circle: P = 2 × π × r baseboard ≈ P - (doors × 3)
Examples
Example 1
12 × 10 ft room perimeter = 44 ft.
Example 2
Radius 5 ft circle circumference ≈ 31.42 ft.
Assumptions
- Door gaps default to 3 ft each for baseboard estimates.
- Does not account for bay windows or curved walls.
FAQ
How is a 12×10 ft room's perimeter calculated?
2×(12+10) = 44 ft before subtracting doors.
Why subtract doors?
Baseboard and wallpaper usually stop at door openings. Enter door widths to exclude them.
Does this work for paint?
Perimeter helps for baseboard. Wall paint needs height and openings; use the Paint calculator.
What about bay windows?
Measure each wall segment and add them, or approximate with the closest rectangle and adjust.