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Free Contractor Tool

Square Footage Calculator

Add multiple rooms or sections — rectangles, circles, and triangles — to get total square feet, square yards, and square meters. Enter a price per square foot and a waste factor to estimate material cost and the quantity you should actually order.

Build Contractor Proposals Faster
Contractor team measuring and planning square footage for a job at a work site

Calculate Total Square Footage

Add a row for each room or section, pick its shape, and enter dimensions in feet. The tool sums the total square footage and converts it to square yards and square meters. Results update instantly.

Areas to measure

120 ft²
180 ft²

Enables total material / project cost.

Adds a waste allowance to the square footage you order.


Results

Total sq ft

300

Square yards

33.33

Square meters

27.87

Material cost

Enter price above

Areas counted

2

Roofing squares

3

Sq ft with waste

Cost with waste

How to Measure Square Footage

Square footage is simply length times width for a rectangular area. For a whole job, measure each space, calculate it, and add the areas together.

ShapeFormulaMeasureExample
Rectangle / SquareLength × WidthBoth sides in feet12 × 10 = 120 ft²
Circleπ × radius²Diameter in feet10 ft dia = 78.54 ft²
Triangle0.5 × base × heightBase and height in feet12 × 8 ÷ 2 = 48 ft²

How to measure square footage on a job

Measure the length and width of each room in feet and multiply them together. For an entire job, measure every room or section, calculate each area, and add the totals. Break irregular spaces into simple rectangles, circles, and triangles, then sum them.

Subtract non-usable areas — islands, closets you are not covering, or built-ins — so you are not paying for material you will not install. Always double-check your tape measurements before ordering.

Square feet vs square yards vs squares

One square yard equals 9 square feet, so divide square footage by 9 to get square yards — useful for carpet, which is often priced per square yard. One roofing square equals 100 square feet, so divide by 100 to get squares for roofing estimates.

One square meter equals about 10.76 square feet (1 ft² = 0.092903 m²). This calculator shows square feet, square yards, and square meters at once so you can quote in whatever unit your supplier uses.

Are You a Contractor? Turn Accurate Measurements Into Faster Proposals

Calculating square footage is one step — building a winning proposal from your measurements is another. SubcontractorHub lets contractors build professional, branded proposals on a tablet at the job site, with material quantities, labor, and financing options included.

Present good-better-best options, collect a digital signature on the spot, and send the signed job straight to operations with zero re-entry.

See How It Works

Build accurate proposals in minutes

Include material quantities, labor, and markup automatically

Present financing and monthly payments at the job site

Digital signature collected on the spot

Signed job flows directly to operations — zero re-entry

Common Questions About Square Footage

How do you calculate square footage?

For a rectangular or square area, multiply length by width in feet: square footage = length × width. For a circle, use π × radius² (radius is half the diameter). For a triangle, use 0.5 × base × height. To get a whole-job total, calculate each room or section and add them together. This calculator sums multiple areas of any shape automatically.

How many square feet are in a square yard?

There are 9 square feet in 1 square yard, because a square yard is 3 ft × 3 ft. To convert square feet to square yards, divide by 9 — for example, 900 ft² ÷ 9 = 100 square yards. Carpet is often priced per square yard, so this conversion matters when estimating cost.

How do I calculate square footage of multiple rooms?

Measure each room, calculate its square footage (length × width for rectangular rooms), and add all the totals together. For irregular spaces, break them into rectangles, circles, and triangles, calculate each, and sum. Add a row per room in this calculator and it totals everything for you.

What is a roofing square?

A roofing square equals 100 square feet. Roofers price and order material in squares rather than square feet, so divide total square footage by 100 to get squares — a 2,400 ft² roof surface is 24 squares. Remember the roof surface is larger than the building footprint because of the slope.

How do I calculate square footage for flooring, paint, or material?

Start with the total square footage of the surface — floor area for flooring, wall area for paint — then multiply by the price per square foot for material cost, and add a 5–10% waste factor for cuts and mistakes. This calculator includes optional price and waste inputs so you see both the adjusted square footage and the estimated cost.

How much extra should I add for waste?

A 5–10% waste factor is standard. Use around 5% for simple rectangular rooms with few cuts, and 10% or more for diagonal or patterned installs and rooms with many corners and obstructions — up to about 15% for intricate tile. This calculator applies your chosen percentage to show the quantity you should actually order.

Are You a Contractor Looking to Quote Faster and Close More?

SubcontractorHub helps contractors turn field measurements into accurate proposals, present financing, and close jobs on-site — built for the way contractor sales actually works.

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Square footage results are estimates based on the dimensions you enter. Verify all measurements on site and confirm material quantities and waste allowances against manufacturer specifications before ordering.