# Square Footage Calculator Calculate area for any shape or room. Multi-room totals, unit conversion, waste factor, and cost estimate. Free, no signup. Canonical page: https://invoicemama.com/calculators/square-footage-calculator This is a free browser calculator. Treat results as planning aids and confirm figures against your own measurements, codes, and professional judgment. ## How to calculate square footage with this calculator Select a shape, enter dimensions in any unit, and get instant area in sq ft, sq yd, sq m, acres, and optional material cost. ### 1. Select your shape Choose rectangle, square, circle, triangle, trapezoid, border, parallelogram, or sector. The diagram updates so you know which dimension maps to each input. ### 2. Enter dimensions Type length, width, diameter, or other measurements. Pick inches, feet, yards, centimeters, or meters per field. Toggle multi-room mode to add every room in a house. ### 3. Get area and cost See square feet, square yards, square meters, and acres instantly. Add an optional waste factor and price per unit for a material cost estimate you can share or invoice. ## Frequently asked questions ### How do I calculate square footage of a room? Measure the room length and width in feet, then multiply them together. A 12 ft by 14 ft bedroom is 168 square feet. For irregular shapes, break the room into rectangles, calculate each section, and add the totals. Our calculator handles rectangles, L-shapes via multi-room mode, and ten other shapes with automatic unit conversion. ### How do I calculate square footage of a house? Measure each room or zone separately, then add every area together for the total livable square footage. Use multi-room mode to list bedrooms, bathrooms, kitchen, and living areas row by row with a running grand total. Exclude garages, unfinished basements, and open porches unless your local listing rules say otherwise. ### How many square feet is a 12x12 room? A 12 by 12 room is 144 square feet because 12 x 12 = 144. That equals 16 square yards or about 13.38 square meters. At a common flooring waste factor of 10%, you would order roughly 158 sq ft of material to cover the same room with cuts and spare tiles included. ### How do I convert square footage to square yards? Divide square feet by nine to get square yards. One square yard equals nine square feet. For example, 270 sq ft / 9 = 30 sq yd. Carpet and some turf products are priced per square yard, so this conversion matters when you compare quotes from different suppliers. ### How do I calculate square footage for flooring? Measure each room length and width, multiply for area, then add every room total. Add a waste factor of 10-15% for straight layouts or up to 20% for diagonal tile and herringbone patterns. Enter your price per square foot or square yard to see an estimated material cost before you order. ### What is included in a home's square footage for real estate? ANSI and Fannie Mae guidelines count finished, heated, above-grade living area that is accessible from the main house. Basements, garages, attics, and open porches are usually excluded unless they are finished to the same standard and included per local MLS rules. Always confirm with your appraiser or agent. ### How do I measure square footage of an irregular or L-shaped room? Divide the space into simple rectangles or squares. Measure each section, calculate its area, and add the results. In multi-room mode, add one row per section and the calculator totals everything automatically. For curved walls, approximate with a rectangle or use the sector shape for pie-slice areas. ### How many square feet are in an acre? One acre equals 43,560 square feet. To convert acres to square feet, multiply by 43,560. A half-acre lot is 21,780 sq ft. Landscapers and land buyers use this conversion constantly when comparing parcel sizes or estimating sod, seed, and mulch coverage for large outdoor projects. ### How do I add a waste factor when ordering flooring or tile? Calculate the base square footage first, then multiply by one plus your waste percentage. For 10% waste on 200 sq ft: 200 x 1.10 = 220 sq ft to order. Straight plank flooring often needs 10%, while diagonal tile may need 15% or more. Our calculator shows base area and adjusted area side by side. ### How do I calculate price per square foot? Divide the total project cost by the square footage covered. If flooring materials cost $1,320 for 240 sq ft installed, the price per square foot is $5.50. Reverse the math by entering your per-unit price in the calculator to estimate total material cost from measured area plus optional waste. ## Turn Measurements Into a Paid Invoice You measured the space, now get paid for it. Invoice Mama turns your square footage estimate into a professional flooring or renovation invoice in seconds. - [Create your first invoice free](https://app.invoicemama.com/sign-up) --- Invoice Mama is invoicing software for contractors, freelancers, and small businesses. It is not a tax, legal, or accounting firm. For current pricing, use the live pricing page. **More:** [Home](https://invoicemama.com/) - [Pricing](https://invoicemama.com/pricing) - [Guides](https://invoicemama.com/guides) - [Tools](https://invoicemama.com/tools) - [Calculators hub](https://invoicemama.com/calculators)