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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Square Feet to Square Yards for a Rectangle CalculatorConvert a rectangle's dimensions in feet to square yards instantly. Enter length and width in feet to get the area in square yards (1 sq yd = 9 sq ft).
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Rectangular Field / Plot Area CalculatorCalculate the area of a rectangular field or plot of land from its length and width in meters, feet, or yards. Get results in m², hectares, and acres.
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Paint Area Calculator with Door & Window DeductionsCalculate the true paintable wall area by subtracting door and window openings from the gross wall area. Free, metric, and easy to use.
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Paint Calculator with Multiple CoatsCalculate how much paint you need for a wall with multiple coats. Enter width, height, coats, and coverage to get gallons or liters required.
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Area of an Octagon CalculatorCalculate the area of a regular octagon from its side length using A = 2(1+√2)·s². Instant results with perimeter and worked example.
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Area of a Semicircle CalculatorCalculate the area of a semicircle from its radius using A = ½πr². Also shows diameter and perimeter. Fast, free, and accurate semicircle area tool.
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Area of an Ellipse CalculatorCalculate the area of an ellipse instantly using A = π·a·b. Enter the semi-major and semi-minor axes to get area plus an approximate perimeter.
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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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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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Rectangle Square Feet to Square Meters CalculatorConvert a rectangle's dimensions in feet to area in square meters. Enter length and width to get instant ft² and m² results with the 0.092903 factor.
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Rectangle Square Meters to Square Feet CalculatorConvert a rectangle's area from square meters to square feet. Enter length and width in meters to get the total area in ft² instantly.
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Countertop Square Footage CalculatorCalculate countertop square footage by adding up each section's length × width. Includes waste overage, square meters, and total square inches.
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Guntha to Square Feet CalculatorConvert Guntha to square feet instantly. 1 Guntha = 1,089 ft². A traditional Indian land-area unit used in Maharashtra, Karnataka & beyond.
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Kanal to Square Feet CalculatorConvert Kanal to square feet (ft²) instantly. 1 Kanal = 5,445 sq ft, the standard land unit used in Pakistan and northern India. Also shows yd² and m².
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Hemisphere Surface Area CalculatorCalculate the total surface area of a hemisphere (3πr²) plus its curved and flat-base areas from the radius. Fast, accurate, and free.
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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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Heron's Formula CalculatorFind the area of any triangle from its three side lengths using Heron's formula. Free calculator showing area, semi-perimeter and perimeter instantly.
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Square Centimeters of a Rectangle CalculatorCalculate the area of a rectangle in square centimeters (cm²) instantly. Enter length and width in cm to get the area using A = l × w.
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Square Inches of a Rectangle CalculatorCalculate the area of a rectangle in square inches by multiplying length × width. Instant results plus a square-feet conversion.
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Square Feet per Gallon Paint CalculatorFind out how many gallons of paint you need. Enter wall area, coverage per gallon, and coats to get the exact amount of paint to buy.
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Wall Tile CalculatorCalculate how many wall tiles you need for a backsplash or feature wall. Enter wall size, tile size, and waste % to get the exact tile count.
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Mosteller Body Surface Area (BSA) CalculatorCalculate body surface area (BSA) in m² using the Mosteller formula from weight (kg) and height (cm). Fast, accurate, and clinically common.
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Square Footage CalculatorCalculate square footage from length and width in feet. Get instant area in sq ft, square yards, and square meters for any room or space.
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Grass Seed CalculatorCalculate how many pounds of grass seed you need based on lawn area (length × width) and seeding rate per 1,000 square feet. Free and instant.
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.
