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Total Square Footage Calculator
Break complex floorplans down into simple rooms. Add up rectangles, triangles, and circles to find the exact total square footage of any space.
Total Area Calculator
How to Calculate Square Footage
Square footage is a measurement of two-dimensional area. Knowing the exact square footage of a room, house, or lot is critical for buying flooring, painting walls, estimating HVAC needs, or listing property for sale.
Basic Formulars by Shape
Not all rooms are perfect rectangles. To calculate the total area of a complex floorplan, you must break the space down into simple geometric shapes, calculate their individual areas, and add them all together.
- Rectangles & Squares:
Area = Length × Width. This is the most common room shape. Just measure the two adjacent walls and multiply them. - Triangles:
Area = (Base × Height) / 2. Useful when your layout includes angled walls, bay windows, or unique plot boundary tapers. - Circles:
Area = π × Radius². Helpful for circular stages, patios, or large round planters. Measure from the exact center to the edge to find the radius.
Real World Tips
- Measure in Feet: To get square feet, all your initial measurements must be in feet. If measuring in inches, divide the final square inches by 144 to convert it to square feet.
- Ignore Minor Inset/Outset: Unless you are buying precise materials like expensive tile, it is usually okay to ignore small architectural indents or fireplace bump-outs when estimating whole-home square footage.
- The 10% Waste Rule: If you are buying flooring (hardwood, carpet, tile) based on your square footage calculation, always add 10% to the final number. This accounts for material wasted during cuts and installation errors.