Square Footage Calculator
Add up the area of every room to get total square footage — with instant conversion to square meters, acres, and roofing squares.
Add 5–10% for flooring/tile cuts and offcuts.
How to Calculate Square Footage
For any rectangular room, square footage is simply length × width. To find the total square footage of a whole home or floor, calculate each room separately and add the areas together — which is exactly what this calculator does. For L-shaped or irregular rooms, split the space into rectangles, measure each, and sum them.
When you're buying materials like flooring or tile, add a waste factor of 5–10% (more for diagonal layouts or busy patterns) so you have enough for cuts and mistakes. One roofing "square" equals 100 square feet, and an acre is 43,560 square feet — both are shown above automatically.
Frequently Asked Questions
How do I calculate the square footage of a room?
Measure the room's length and width in feet and multiply them. A room that is 12 ft by 14 ft is 168 square feet. For multiple rooms, calculate each one and add the totals together.
How do I convert square feet to square meters?
Multiply square feet by 0.0929 to get square meters (or divide by 10.764). This calculator shows both units at once, so you never have to convert by hand.
How much waste should I add when ordering materials?
A 10% overage is standard for flooring and tile to cover cuts and breakage. Use 5% for simple straight layouts and 15% or more for diagonal patterns, herringbone, or rooms with many angles.
Turn Your Measurements Into a Real Floor Plan
Once you know your dimensions, generate a labeled, to-scale floor plan in seconds — then export it to DXF or build it in 3D. No CAD experience needed.
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