Geometry Calculator
Calculate area, perimeter, and other measurements for various geometric shapes.
Results
Basic Measurements
Additional Measurements
Geometry Calculator Features | CalculatorDekho
CalculatorDekho's Geometry Calculator is built to simplify complex math problems for both professionals and beginners. Whether you need to measure a room for renovation, design a mechanical part, or help your child with homework, this tool delivers accurate results in seconds.
Shapes Covered
- Rectangle – four right angles.
- Triangle – three sides, using Heron’s formula when needed.
- Trapezoid – one pair of parallel sides.
- Circle – perfect round shape.
- Sector – a slice of a circle.
- Ellipse – oval shape with two axes.
- Parallelogram – opposite sides parallel.
How to Use
Using the Geometry Calculator is simple:
- Select the shape from the dropdown or menu.
- Enter measurements (e.g., length, width, radius).
- Verify labels on the live preview diagram.
- Click Calculate and view results instantly.
- Copy or note down your results for reference.
Input Fields & Formulas
Each shape has its own set of inputs and formulas:
Rectangle
Area: l × w
Perimeter: 2 × (l + w)
Triangle (Heron’s Formula)
Area: √[s(s–a)(s–b)(s–c)], where s = (a+b+c)/2
Perimeter: a + b + c
Trapezoid
Area: (b1 + b2) / 2 × h
Perimeter: b1 + b2 + side1 + side2 (enter side lengths manually)
Circle
Area: π × r²
Circumference: 2 × π × r
Sector
Area: (θ / 360) × π × r²
Arc Length: (θ / 360) × 2 × π × r
Ellipse
Area: π × a × b
Circumference (approx): π [3(a + b) – √((3a + b)(a + 3b))]
Parallelogram
Area: b × h
Perimeter: 2 × (b + side length) (enter side length manually)
Detailed Examples
1. Flooring a Room (Rectangle)
You need carpet for a room measuring 12 ft by 15 ft. Input these values to find area = 12 × 15 = 180 ft². The perimeter (12+15+12+15) = 54 ft helps when you buy trim.
2. Triangular Plot (Triangle)
Land with sides 50 m, 60 m, and 70 m. s = (50+60+70)/2 = 90. Area = √[90×(90–50)(90–60)(90–70)] ≈ 1,496 m².
3. Circular Garden Bed (Circle)
Radius = 3 m. Area = π×3² ≈ 28.27 m². Circumference = 2π×3 ≈ 18.85 m.
4. Pie Slice (Sector)
Slice from a 10-inch pizza at 45°. Area = (45/360)×π×10² ≈ 39.27 in².
Common Area Units
| Unit | Equivalent in m² |
|---|---|
| Square meter | 1 |
| Hectare | 10,000 |
| Square kilometer | 1,000,000 |
| Square foot | 0.092903 |
| Square yard | 0.836127 |
| Acre | 4,046.86 |
| Square mile | 2,589,988 |
Geometry Calculator – Frequently Asked Questions (FAQs)
1. How do you calculate the area of a circle?
Answer: Area = π × r², where r is the radius.
2. How do you calculate the circumference of a circle?
Answer: Circumference = 2 × π × r or π × d, where d is the diameter.
3. How do you calculate the area of a square?
Answer: Area = a², where a is the side length.
4. How do you calculate the perimeter of a square?
Answer: Perimeter = 4 × a.
5. How do you calculate the area of a rectangle?
Answer: Area = l × w, where l is length and w is width.
6. How do you calculate the perimeter of a rectangle?
Answer: Perimeter = 2 × (l + w).
7. How do you calculate the area of a triangle?
Answer: Area = ½ × b × h, where b is base and h is height.
8. How do you calculate the area of a triangle using Heron’s formula?
Answer: First calculate s = (a + b + c) / 2, then Area = √[s(s–a)(s–b)(s–c)].
9. How do you calculate the area of a parallelogram?
Answer: Area = base × height.
10. How do you calculate the area of a trapezoid?
Answer: Area = ½ × (a + b) × h, where a and b are the parallel sides.
11. How to find the sum of interior angles of a polygon?
Answer: Sum = (n – 2) × 180°, where n is the number of sides.
12. How to find each interior angle of a regular polygon?
Answer: Each angle = [(n – 2) × 180°] / n.
13. How to calculate the diagonal of a rectangle?
Answer: Diagonal = √(l² + w²).
14. How do you calculate the volume of a cube?
Answer: Volume = a³.
15. How do you calculate the surface area of a cube?
Answer: Surface Area = 6 × a².
16. How do you calculate the volume of a cuboid?
Answer: Volume = l × w × h.
17. How do you calculate the surface area of a cuboid?
Answer: Surface Area = 2 × (lw + lh + wh).
18. How do you calculate the volume of a cylinder?
Answer: Volume = π × r² × h.
19. How do you calculate the surface area of a cylinder?
Answer: Surface Area = 2 × π × r × (r + h).
20. How do you calculate the volume and surface area of a sphere?
Answer: Volume = ⁴⁄₃ × π × r³, Surface Area = 4 × π × r².
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