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Area of a Rectangle Calculator

Use this calculator to easily calculate the area of a rectangle, given its length and width in any metric: mm, cm, meters, km, inches, feet, yards, miles, etc. Provide length and width to compute the rectangle’s area instantly using length × width.

Area: N/A

Real-World Example

Suppose you are designing a rectangular garden that measures 20 feet in length and 15 feet in width. The area of a rectangle is calculated with the formula A = L × W, where L is the length and W is the width. Substituting the values, A = 20 × 15 = 300 ft². The calculator shows this instantly, helping you know the exact ground space you can use for planting.

How the Formula Works

The formula for the area of a rectangle is A = L × W. This is because the shape is made up of equal rows and columns of units, and multiplying length by width counts all of them. For example, if a rectangle is 5 meters long and 4 meters wide, A = 5 × 4 = 20 m². The calculator applies this same rule but also manages conversions automatically.

Home Project Uses

When planning to tile or carpet a rectangular room, the area is essential. Suppose your living room is 12 feet long and 10 feet wide. By using the calculator, you enter L = 12 ft and W = 10 ft. The area is A = 12 × 10 = 120 ft². Knowing this lets you purchase exactly the right number of tiles or carpet rolls, avoiding waste or shortage.

Learning Geometry

Students often use the rectangle calculator to check classroom problems. A teacher might assign: “Find the area of a rectangle with sides 8 cm and 6 cm.” The formula is A = L × W, so A = 8 × 6 = 48 cm². Typing these numbers into the calculator confirms the answer, reinforcing the formula and building confidence in solving geometry exercises.

Unit Conversions

This calculator also solves tricky unit problems. If a rectangle’s length is given as 3 meters and the width as 250 centimeters, the formula A = L × W still applies, but the units must match. The calculator converts 250 cm into 2.5 m, then A = 3 × 2.5 = 7.5 m². Without needing to do conversions by hand, the tool gives a precise and reliable result.

Comparing Spaces

The rectangle calculator is also useful for comparing areas. Consider two plots: Plot A is 40 ft by 30 ft, so A = 40 × 30 = 1200 ft². Plot B is 25 ft by 50 ft, so A = 25 × 50 = 1250 ft². The calculator shows that Plot B is slightly larger, helping buyers or builders make better decisions when choosing between rectangular spaces.

Area of a Square Calculator | Area of a Triangle Calculator | Area of a Rhombus Calculator | Area of a Trapezoid Calculator | Area of a Parallelogram Calculator

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