Home & Renovation
Square Footage Calculator
Calculate square footage, perimeter, and square meters for any room.
Square footage is needed for flooring, paint, tile, and renovation estimates. This calculator handles rectangular, L-shaped, and multiple-room calculations.
Floor Area
180 sq ft
- square Meters
- 16.72 m²
- perimeter
- 54 ft
- baseboard
- 54 linear ft of baseboard needed
Formula and method
Area = Length × Width; Perimeter = 2(L + W)
Standard rectangle formula. For irregular rooms, break into rectangles and sum the areas.
Worked examples
Living room
- Length (ft):
- 18
- Width (ft):
- 14
Floor Area: 252 sq ft
Kitchen
- Length (ft):
- 12
- Width (ft):
- 10
Floor Area: 120 sq ft
Assumptions and limits
- Rectangular room
- No obstacles or irregular shapes
This tool provides an educational estimate. Rules, rates and personal circumstances can change the answer. Review the assumptions before relying on a result. Report a correction.
Common mistakes to avoid
- Measuring at the widest point for irregular rooms — break irregular shapes into rectangles.
- Forgetting to add waste factor for flooring — add 10% for rectangular rooms, 15-20% for diagonal layouts.
Frequently asked questions
How much extra flooring should I order?
Rectangular rooms: add 10%. Diagonal or complex layouts: add 15-20%. Always order from the same dye lot — it is hard to match later.
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