Calculate the area of any space in square feet, square meters, square yards, or acres. Choose your shape and enter dimensions to get instant results.
Measuring square footage is something you'll need for a ton of practical projects: buying flooring, painting walls, planning a garden, or figuring out how much rent should cost. The good news is that it's straightforward once you know the shape you're working with.
For most rooms, you just need a tape measure and a few minutes. Measure the length and width in feet, multiply them together, and you've got your square footage. For odd-shaped spaces, break them into smaller rectangles, calculate each one, then add them up.
Calculate area for rectangles, circles, triangles, and trapezoids
Instantly see results in sq ft, sq m, sq yards, and acres
Perfect for flooring, painting, landscaping, and more
Knowing typical room sizes helps you double-check your measurements and plan projects more accurately.
| Room/Space | Typical Size (ft) | Square Footage | Notes |
|---|---|---|---|
| Single Bedroom | 10 × 10 | 100 sq ft | Fits a bed and small dresser |
| Master Bedroom | 14 × 16 | 224 sq ft | Fits king bed and furniture |
| Living Room | 16 × 20 | 320 sq ft | Average for mid-size homes |
| 1-Car Garage | 12 × 20 | 240 sq ft | Tight fit for larger vehicles |
| 2-Car Garage | 20 × 20 | 400 sq ft | Standard size |
| Studio Apartment | 20 × 25 | 500 sq ft | Typical studio in a city |
It's the oldest advice for a reason. Measure each dimension at least twice and use the average if they differ slightly.
Walls aren't always perfectly straight. For flooring projects, measure along the floor rather than at waist height for the most accurate number.
L-shaped rooms or irregular spaces? Divide them into rectangles, calculate each section separately, then add the areas together.
When buying materials like flooring or tile, always add about 10% extra to account for cuts, mistakes, and pattern matching.
Break the room into smaller rectangles or triangles. Measure each section separately, calculate the area of each, then add them all together. For L-shaped rooms, divide into two rectangles. For rooms with angled walls, use the triangle formula for the angled portion.
Linear feet measures length in one direction only (like the length of a wall). Square feet measures area (length times width). When buying baseboard trim, you'd use linear feet. When buying floor tiles, you'd use square feet.
Divide the square footage by 10.764 to get square meters. For example, 200 sq ft divided by 10.764 equals about 18.58 square meters. This calculator does this conversion automatically for you.
One acre contains 43,560 square feet. To put that in perspective, an acre is roughly the size of a football field without the end zones (which is 48,000 sq ft). A quarter-acre lot, common in suburbs, is about 10,890 square feet.
It depends on the purpose. For real estate listings, closets are usually included in the room's square footage if they have a standard ceiling height. For flooring projects, measure the closet separately since you'll need material for that floor too. Always measure what you actually plan to cover.
A standard living room measures 15 ft long by 12 ft wide.
Result180 sq ft (about 16.72 sq m)
Multiply length by width: 15 × 12 = 180 sq ft. To convert to metric, divide by 10.7639: 180 ÷ 10.7639 ≈ 16.72 sq m. Add roughly 10% extra (about 18 sq ft) when ordering flooring to cover cuts and waste.
Use a steel tape measure along the floor, measure wall-to-wall in feet (with inches as a decimal, e.g. 12 ft 6 in = 12.5 ft), then multiply length by width. Measure each dimension twice and average the readings if walls aren't perfectly parallel.
Split the floor plan into rectangles (or triangles for angled walls), calculate each area separately, and sum them. For an L-shape, draw a line that breaks the L into two rectangles, find each area, and add. This rectangle-sum method handles almost any residential layout.
One square meter equals exactly 10.7639 square feet (since 1 ft = 0.3048 m, defined by NIST SP 811). To convert sq ft to sq m, divide by 10.7639. To go the other way, multiply by 10.7639. A 180 sq ft room is roughly 16.72 sq m.
Gross area includes everything inside the exterior walls (including wall thickness, garages, and unfinished basements). Livable or finished area, as defined by ANSI Z765, counts only heated, finished space measured to the exterior of the perimeter walls. Real estate listings should disclose which standard is used.
Under ANSI Z765, finished basements are reported separately from above-grade finished area, and garages are excluded from livable square footage entirely. NAR appraisal guidance follows the same convention so appraisers don't compare an above-grade ranch to a home with a finished walkout basement.
Round only the final result, not intermediate measurements. ANSI Z765 recommends reporting finished area to the nearest whole square foot. For ordering materials, round up (not to the nearest), then add a 10% waste factor on top to cover cuts and pattern matching.
For flooring, paint, and DIY projects, measurements to the nearest inch (about 0.083 ft) are plenty accurate. For appraisals or real estate disclosure, ANSI Z765 calls for measurements to the nearest inch with the final area reported to the nearest whole square foot.
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