Area Calculator
Use this area calculator to calculate the area of common shapes including rectangles, squares, circles, triangles, trapezoids, parallelograms, ellipses and sectors. Get results in square feet, square inches, square yards, square meters and acres.
Area Calculator
Choose a shape and enter your measurements
Use quantity when calculating multiple identical shapes.
How to Calculate Area
Area measures the amount of two-dimensional surface inside a shape. The formula depends on the shape you are measuring. Enter the dimensions using the same unit and the calculator converts the result into common area units automatically.
For a rectangular room, floor, lot, or property, multiply length by width. For example, a 40-foot by 60-foot property has an area of 2,400 square feet. If you need to work with square-foot measurements directly, you can also use our Square Footage Calculator.
Common Area Formulas
Rectangle
Area = Length × Width
Square
Area = Side²
Circle
Area = π × r²
Triangle
Area = ½ × Base × Height
Trapezoid
Area = ½ × (Base 1 + Base 2) × Height
Parallelogram
Area = Base × Height
Common Construction Uses
Flooring
Calculate floor area before estimating tile, flooring or other materials. For tile quantity and coverage estimates, use the Tile Calculator.
Painting
Determine the surface area of walls, ceilings and other surfaces. Once you know the surface area, the Paint Calculator can help estimate paint requirements.
Concrete
Find surface area before calculating the volume of a slab, footing or other concrete element. For material volume, continue with the Concrete Calculator.
Land & Property
Use an area calculator to estimate the size of residential lots, building sites, rooms, floor plans and other measured properties. Enter the length and width using the same unit to calculate square feet, square meters, square yards and acres.
Land & Property Area Calculator
This area calculator can be used as a land area calculator for rectangular plots, residential lots, building sites and other property measurements. For a rectangular property, multiply the length by the width to find the total area.
For example, a 40 ft × 60 ft lot contains 2,400 square feet. A 30 ft × 40 ft property contains 1,200 square feet. These measurements can then be converted to square meters, square yards and acres using the calculator above.
How to Calculate Land Area in Square Feet
Measure the property's length and width in feet, then multiply the two measurements. For example:
Width: 80 ft
Area: 50 × 80 = 4,000 square feet
If the property is irregular rather than rectangular, divide it into smaller rectangles, triangles or other measurable shapes. Calculate each section separately and add the areas together.
For floor plans and room measurements, you can also use the Square Footage Calculator to calculate individual spaces and compare their total floor area.
Square Feet, Square Meters and Acres
Area can be expressed in several units depending on the project. Square feet are commonly used for rooms, buildings and property measurements in the United States, while square meters are common in metric applications. Larger land areas may also be described in acres.
Square Feet
Useful for rooms, floors, buildings and residential property measurements.
Square Meters
A common metric unit for measuring floor, building and property area.
Acres
A larger land-area unit often used for property and agricultural measurements.
Floor Plan and Room Area
To calculate the area of a rectangular room, measure its length and width and multiply them. For a floor plan with several rooms, calculate each room separately and add the results to estimate the total floor area.
For example, a room measuring 12 ft × 15 ft has an area of 180 square feet. For more direct room and square-foot calculations, use the Square Footage Calculator.
Area Calculator FAQ
How do I calculate the area of a rectangle?
Multiply the rectangle's length by its width. For example, a 20-foot by 10-foot rectangle has an area of 200 square feet.
How do I calculate land area?
For a rectangular plot, multiply the length by the width using the same measurement unit. A 40 ft × 60 ft lot, for example, contains 2,400 square feet. For irregular land, divide the property into smaller measurable shapes and add their areas together.
Can I use an area calculator for real estate property?
Yes. An area calculator can estimate the size of rectangular lots, residential properties, rooms, building sites and floor plans when you have the required measurements.
How do I calculate land area in square feet?
Measure the land length and width in feet and multiply them. For example, 50 ft × 80 ft = 4,000 square feet.
Can I use this for a floor plan or room area?
Yes. Measure each room's length and width, calculate the area of each room, and add the results for the total floor area. The Square Footage Calculator can also be used for direct square-foot calculations.
What is the difference between area and perimeter?
Area measures the surface inside a shape, while perimeter measures the distance around its boundary.
Can I calculate area in meters?
Yes. Select meters as the measurement unit. The calculator converts the result to square meters and other common area units.
What is the formula for a circle?
The area of a circle is π multiplied by the radius squared: A = πr².
Results are mathematical estimates based on the measurements entered. Verify dimensions and project requirements before ordering materials or beginning construction work.