Why use our Free Area Calculator?
Finding the precise area of different shapes can be deceptively difficult without proper tools.
Even small calculation mistakes can lead to significant issues—from ordering insufficient materials to creating flawed designs.
Our Area Calculator eliminates these problems by providing exact area measurements for circles, triangles, rectangles and more in seconds, helping you save money on materials and complete your projects with precision.
Area Calculators
Essential Formulas for Calculating the Area of Common Shapes
Understanding how to calculate the area of various shapes is fundamental in fields ranging from architecture to everyday problem-solving.
Whether you’re designing a garden, planning a room layout, or simply satisfying your curiosity, knowing these formulas can be incredibly useful.
Using our free Area Calculator, you can know that you’ve calculated the precise area of any shape.
Below, we break down the formulas for calculating the area of seven common shapes: Rectangle, Triangle, Trapezoid, Circle, Sector, Ellipse, and Parallelogram. Additionally, we’ll explain each formula to ensure clarity and ease of use.

How to calculate the area of a Rectangle
Formula:
Area = Length × Width
Explanation:
A rectangle’s area is found by multiplying its length by its width. This straightforward formula applies whether you’re dealing with metric units (meters) or imperial units (feet).
Example:
If a rectangle has a length of 5 meters and a width of 3 meters:
Area = 5 × 3 = 15 square meters
How to calculate the area of a Triangle
Formula:
Area = 0.5 × Base × Height
Explanation:
To calculate the area of a triangle, multiply the length of its base by its height and then divide by two. This formula is universally applicable across different unit systems.
Example:
For a triangle with a base of 6 feet and a height of 4 feet:
Area = 0.5 × 6 × 4 = 12 square feet
How to calculate the area of a Trapezoid

Formula:
Area = 0.5 × (Base1 + Base2) × Height
Explanation:
A trapezoid has two parallel sides, known as bases. To find its area, add the lengths of these two bases, multiply by the height, and then divide by two.
Example:
If a trapezoid has bases of 8 meters and 5 meters, with a height of 3 meters:
Area = 0.5 × (8 + 5) × 3 = 19.5 square meters
How to calculate the area of a Circle

Formula:
Area = π × Radius²
Explanation:
The area of a circle is calculated by multiplying π (approximately 3.1416) by the square of its radius. This formula remains consistent regardless of the measurement system used.
Example:
For a circle with a radius of 4 inches:
Area = 3.1416 × 4² = 50.2656 square inches
How to calculate the area of a Sector
Formula:
Area = (π × Radius² × Angle) / 360
Explanation:
A sector is a portion of a circle. To determine its area, multiply π by the square of the radius, then multiply by the central angle in degrees, and finally divide by 360.
Area = (3.1416 × 5² × 60) / 360 = 13.09 square meters
Example:
For a sector with a radius of 5 meters and an angle of 60 degrees:
How to calculate the area of an Ellipse

Formula:
Area = π × Major Axis × Minor Axis
Explanation:
An ellipse has two axes: the major axis (the longest diameter) and the minor axis (the shortest diameter). Multiply π by both these axes to find the area.
Example:
If an ellipse has a major axis of 7 feet and a minor axis of 3 feet:
Area = 3.1416 × 7 × 3 = 65.9736 square feet
How to calculate the area of a Parallelogram

Formula:
Area = Base × Height
Explanation:
Similar to a rectangle, the area of a parallelogram is found by multiplying its base by its height. This formula is simple and effective across different measurement systems.
Example:
For a parallelogram with a base of 10 meters and a height of 4 meters:
Area = 10 × 4 = 40 square meters
Choosing Between Metric and Imperial Units
Each of the formulas above works seamlessly with both metric and imperial units. When selecting units:
• Metric: Use meters for length and width, resulting in area measured in square meters.
• Imperial: Use feet for length and width, resulting in area measured in square feet.
Ensure consistency in the units you choose to maintain accuracy in your calculations.
Practical Tips for Accurate Area Calculations
Double-Check Measurements:
Ensure all measurements are accurate and taken correctly to avoid errors in the final area calculation.
Use the Right Formula:
Different shapes require different formulas. Confirm the shape you’re working with before applying a formula.
Consistent Units:
Stick to one unit system throughout your calculations. Mixing metric and imperial units can lead to incorrect results.
Utilize Online Calculators:
When in doubt, use a free online area calculator like ours! We can provide quick and accurate results. These tools often allow you to switch between unit systems effortlessly.
Conclusion
Calculating the area of various shapes is a valuable skill that simplifies numerous tasks in daily life and professional projects.
By understanding and applying the formulas for rectangles, triangles, trapezoids, circles, sectors, ellipses, and parallelograms, calculate areas with confidence.
Remember to choose the appropriate unit system and ensure all measurements are accurate for the best results.
Which shapes does the Area Calculator support?
The calculator works with basic shapes such as squares, rectangles, triangles, circles, and trapezoids.
How do I input my measurements for each shape?
Each shape needs specific measurements:
Squares and rectangles: length and width
Triangles: base and height
Circles: radius or diameter
Trapezoids: two parallel sides plus height
Can I switch between different units of measurement?
Yes. Our Area Calculator lets you pick your preferred unit such as centimeters, meters, inches, or feet. Use the same unit for all measurements of one shape to get correct results.
How accurate are the calculations from this tool?
The calculator uses standard math formulas to find areas. If you enter correct and consistent measurements, the results will be accurate. For professional uses, it’s good to check with manual calculations or ask an expert.