From tiling a floor to solving a geometry problem, precise area measurements are the starting point. This collection covers everyday shapes — the Circle Area Calculator, Rectangle Area Calculator, and Trapezoid Area Calculator — alongside less-common ones like the Ellipse Area Calculator and Sector Area Calculator.
Browse the most-popular list or open the Trending tab to see what other visitors are measuring. All tools are free, require no sign-up, and work on any device.
- Volume Calculator
- Area Calculator
- Perimeter Calculator
- Surface Area Calculator
- Circle Calculator
- Rectangle Calculator
- Triangle Calculator
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Quadrilateral Area CalculatorCalculate the area of a quadrilateral with precision using the Quadrilateral Area Calculator. Input four side lengths to determine the shape's area easily and accurately.
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Rhombus Area CalculatorCalculate the area of a rhombus easily with this online tool. Input the lengths of two diagonals to instantly determine the rhombus area. Fast, accurate, and free!
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Circle Area CalculatorCalculate the area of a circle quickly and accurately with this Circle Area Calculator. Simply input the radius to determine the precise area of any circular shape.
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Rectangle Area CalculatorEnter length and width to calculate rectangle area and perimeter in seconds. View results and the Area = Length × Width formula to size projects.
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Area of a Sector CalculatorCalculate the area of a circular sector from radius and central angle in degrees or radians. Also gives arc length. Free, instant, with formula and examples.
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Cube Surface Area CalculatorEnter a cube’s side length to instantly calculate its total surface area (A = 6s²). Quick help for geometry, homework, and simple planning.
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Equilateral Triangle Area CalculatorCalculate the area, perimeter, and height of an equilateral triangle from its side length. Free, unit-agnostic geometry tool with worked examples.
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Area of a Square CalculatorCalculate the area of a square instantly with side length using A = s². Also shows perimeter and diagonal. Free, fast, and accurate geometry tool.
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Area of a Pentagon CalculatorCalculate the area of a regular pentagon from its side length. Get area, perimeter and apothem instantly with the exact geometric formula.
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Area Between Two Curves CalculatorCompute the area between two curves f(x) and g(x) over an interval [a,b] using definite integration of |f−g|. Handles crossings automatically.
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Cylinder Lateral Surface Area CalculatorCalculate the lateral (curved) surface area of an open cylinder using A = 2πrh. Enter radius and height for instant results in square units.
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Square Feet to Square Yards ConverterConvert square feet to square yards instantly. Divide ft² by 9 to get yd². Free, accurate area converter for flooring, carpet, and landscaping projects.
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Paint-by-Numbers Acrylic Paint Coverage CalculatorEstimate how much area your acrylic paint covers from mL and coverage per mL. Adjusts for multiple coats. Great for paint-by-numbers and craft projects.
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Square Footage of Walls in a Room Calculator (Wall Area + Drywall Sheets)Calculate how many drywall sheets you need for a room. Enter length, width and wall height, pick a sheet size, add waste — get total sheets fast.
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Net vs Gross Floor Area Calculator (Carpet to Built-up Area)Convert carpet area to built-up and super built-up area using loading and common-area factors. Free real-estate floor-area calculator.
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Annulus (Ring) Area CalculatorCalculate the area of an annulus (ring) from its outer and inner radii using A = π(R² − r²). Also shows ring width and circumferences.
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Isosceles Triangle Area CalculatorCalculate the area of an isosceles triangle easily with base and height inputs. Get accurate results instantly for geometry problems and real-world applications.
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Square Feet to Cents ConverterConvert square feet to cents, the traditional Indian land area unit. 1 cent = 435.6 sq ft. Fast, accurate land area conversion for property in India.
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Acres to Square Yards ConverterConvert acres to square yards instantly. Enter any acreage and get the exact area in square yards using the factor 1 acre = 4,840 yd².
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30-60-90 Triangle Area CalculatorCalculate the area of a 30-60-90 right triangle from the short leg. Get area, long leg, hypotenuse, and perimeter instantly using A = (√3/2)·x².
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Square Centimeters to Square Meters ConverterConvert square centimeters (cm²) to square meters (m²) instantly. Just divide by 10,000. Free, accurate area unit converter with formula and examples.
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45-45-90 Triangle Area CalculatorFind the area of a 45-45-90 right isosceles triangle from a leg or hypotenuse. Uses A = leg²/2 or hypotenuse²/4. Free and instant.
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Square Kilometers to Square Miles ConverterConvert square kilometers (km²) to square miles (sq mi) instantly. Enter an area and get an accurate result using the factor 0.386102159.
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Concrete Slab CalculatorCalculate concrete slab area and volume. Enter length, width, and thickness to get square feet, cubic feet, cubic yards, and bag estimates.
Frequently asked questions
What shapes are covered in this area calculator collection?
You'll find calculators for circles, rectangles, triangles, trapezoids, ellipses, parallelograms, rhombuses, and circular sectors. Whether the task is a renovation estimate, a design project, or a school assignment, the right tool is here and ready to use.
How reliable are the area results?
Each calculator applies the standard mathematical formula for its shape, tested against reference values. For home projects the figures are a solid guide, but for construction, permitting, or safety-critical work, verify against the governing standard and have a qualified engineer review the numbers.
Are these area calculators free to use?
Yes — every calculator here is completely free with no account, no subscription, and no hidden fees. Open any tool, enter your dimensions, and get your area calculation right away.
Is my data stored on your servers?
No. Every calculation happens entirely in your browser. Your input values are never sent to our servers, stored in a database, or shared with any third party. Close the tab and your entries are gone.
How do I find the most-used area calculators?
The default list is sorted by real visitor usage, putting the most popular tools at the top. Switch to the Trending tab for tools gaining momentum right now, or check Recently Added for the latest additions to the collection.
