Square Footage Calculator
Add up square footage for multiple rooms or areas. Supports optional waste factor for flooring and material ordering.
Assumptions
- Each room is rectangular.
- Waste defaults to 0% unless ordering materials.
- Results show ft² and m².
- Irregular rooms should be split into rectangles.
- Ceiling and wall areas are not included unless entered as floor-like rectangles.
Room area = length × width (each room). Total = sum of rooms. With waste: total × (1 + waste%).Two rooms: 12×10 and 10×10
- Room 1 = 120 ft². Room 2 = 100 ft². Total = 220 ft². With 10% waste = 242 ft².
How to measure
Measure each room at the longest points on the floor. For open floor plans, divide visually at logical boundaries or use plan dimensions.
Common mistakes
- Double-counting overlapping areas in open plans.
- Measuring wall-to-wall including unusable niches inconsistently.
- Forgetting closets that will receive the same flooring.
Frequently asked questions
How do I measure L-shaped rooms?
Split into two rectangles, calculate each, and add.
Convert to square meters?
Results include m² automatically from the same inputs.
Include waste here or in the flooring calculator?
Use waste in one place only to avoid double-counting.
Appraisal vs material area?
GLA for appraisals follows specific rules — this is a general area tool.