Calculate square footage and area from construction measurements, including feet, inches, and fractions.
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Enter length and width for rooms, walls, slabs, and panels.
Enter length and width to calculate.
Area measures the amount of surface inside a two-dimensional shape. In construction, area is commonly expressed in square feet and is used for floors, walls, ceilings, slabs, panels, finishes, and general layout. Choose the shape that best matches the measured area, enter the field dimensions, and Skoppe Calculator calculates the square footage automatically.
Rectangle: Area = Length × Width
Triangle: Area = Base × Height ÷ 2
Circle: Area = π × Radius²
Trapezoid: Area = (Side A + Side B) ÷ 2 × Height
Both dimensions have to be in the same unit before they are multiplied. Skoppe Calculator normalizes feet, inches, and fractions first, so 14 ft 6 in and 11 ft 8 in multiply at full precision.
A room measured in construction dimensions:
Length = 14 ft 6 in = 174 in
Width = 11 ft 8 in = 140 in
174 × 140 = 24,360 sq in
24,360 ÷ 144
Room area: ≈ 169.17 sq ftBase = 12 ft
Height = 8 ft
12 × 8 ÷ 2
Triangle area: 48 sq ftDiameter = 10 ft
Radius = 10 ÷ 2 = 5 ft
π × 5²
Circle area: ≈ 78.54 sq ftA square measuring 1 foot by 1 foot. One square foot equals 144 square inches.
A square measuring 1 yard by 1 yard. One square yard equals 9 square feet.
A square measuring 1 inch by 1 inch. Useful for smaller measured surfaces such as openings and panels.
A linear foot measures length. A square foot measures area — length and width together.
Floors: measure room or floor surface area.
Walls: calculate wall surfaces from length × height.
Ceilings: calculate ceiling square footage.
Roof sections: calculate basic measured surface shapes where the dimensions are known.
Slabs & decks: measure plan-area surfaces for patios, pads, and decks.
Openings & panels: calculate doors, windows, sheets, panels, and other rectangular surfaces.
Linear feet measure one-dimensional length. Square feet measure two-dimensional area.
A wall that is 10 ft long and 8 ft high has 10 linear ft of wall length but 80 sq ft of wall surface.
Break irregular shapes into simple rectangles, triangles, or other measurable sections. Calculate each section separately, then add the areas together.
An L-shaped room is Rectangle A plus Rectangle B: run the calculator once for each section and add the two results for the total area.
To exclude doors, windows, openings, or other areas, calculate their area separately and subtract it from the total.
A wall of 160 sq ft with a 15 sq ft window has 145 sq ft of net surface.
| Measurement | Area |
|---|---|
| 10 ft × 10 ft | 100 sq ft |
| 12 ft × 12 ft | 144 sq ft |
| 10 ft × 20 ft | 200 sq ft |
| 20 ft × 20 ft | 400 sq ft |
| 1 sq yd | 9 sq ft |
| 1 sq ft | 144 sq in |
Multiply the length by the width when measuring a rectangle. If the measurements include feet, inches, or fractions, normalize them to a common unit before multiplying.
One square yard equals 9 square feet.
One square foot equals 144 square inches.
Multiply the base by the perpendicular height, then divide by two.
Square the radius and multiply by pi. If you know the diameter, divide it by two to find the radius first.
Yes. Skoppe Calculator supports construction-style dimensional inputs including feet, inches, and common fractions.
Break the room into two or more rectangles, calculate each area separately, then add them together.
Calculate the total wall area, calculate the area of each opening, then subtract the openings from the total.
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