math Calculator

Perimeter Calculator

Calculate perimeter of various shapes.

Perimeter Calculator

Calculate the perimeter of rectangles, squares, and triangles quickly. Enter the shape and dimensions and results update automatically.

Enter values to see results

Perimeter Calculator

Use the Perimeter Calculator to quickly compute the total distance around a shape. This tool supports rectangles, squares, and triangles. Enter the appropriate side lengths and the calculator updates automatically. Results can be downloaded as a PDF and visualized with a bar chart. Get instant results with our user-friendly interface!

Understanding Perimeter

The perimeter is the total distance around the edges of a shape. It's a fundamental concept in geometry and is crucial for various applications, including construction, land measurement, and even in designing simple objects. Knowing how to calculate the perimeter can help you better understand the dimensions of the objects around you.

This Perimeter Calculator simplifies this process, making it quick and straightforward to find the required perimeter for common geometric shapes. Whether you are a student, a teacher, or a DIY enthusiast, our calculator is designed to assist you in your mathematical journey.

How it works

The calculator uses standard perimeter formulas:

  • Rectangle: Perimeter = 2 × (length + width)
  • Square: Perimeter = 4 × side
  • Triangle: Perimeter = side1 + side2 + side3
Perimeter = sum of all sides

Examples

Rectangle

Length = 10, Width = 5 → Perimeter = 2 × (10 + 5) = 30 units

Square

Side = 8 → Perimeter = 4 × 8 = 32 units

Triangle

Sides = 3, 4, 5 → Perimeter = 3 + 4 + 5 = 12 units

Tips for Accurate Results

  • Ensure all side lengths are entered using the same unit (e.g., meters or feet).
  • Non-negative values are required; the calculator will not return a result for invalid inputs.
  • For triangles, provide all three sides to compute the perimeter.

Frequently Asked Questions

Can I use different units for different sides?

No. Enter all dimensions using the same unit to get a meaningful perimeter. Convert units before calculating if needed.

What if I only know the diagonal of a rectangle?

The perimeter cannot be determined from the diagonal alone. You need both side lengths or enough information to derive them (e.g., diagonal and one side, using Pythagoras).

Do you support circles or other shapes?

This calculator focuses on polygons: rectangles, squares, and triangles. For circles, you would use circumference = 2 × π × radius — consider using or creating a circumference calculator for that purpose.

Use Cases for the Perimeter Calculator

This Perimeter Calculator can be utilized in various scenarios, including:

  • Students learning geometry concepts in schools.
  • Engineers and architects designing and assessing spaces.
  • DIY enthusiasts looking to build or remodel spaces.
  • Anyone needing quick calculations for fencing, landscaping, or painting projects.

SEO Summary

Perimeter Calculator for rectangles, squares, and triangles offers instant calculation results, PDF export, and easy visualization through charts. Perfect for geometry students, professionals, and DIY projects.

Frequently Asked Questions

Can I use different units for different sides?

No. Enter all dimensions using the same unit to get a meaningful perimeter. Convert units before calculating if needed.

What if I only know the diagonal of a rectangle?

The perimeter cannot be determined from the diagonal alone. You need both side lengths or enough information to derive them (e.g., diagonal and one side, using Pythagoras).

Do you support circles or other shapes?

This calculator focuses on polygons: rectangles, squares, and triangles. For circles, you would use circumference = 2 × π × radius — consider using or creating a circumference calculator for that purpose.

Meet the Expert

Prof. Geometry

Prof. Geometry

Geometry Expert

Professor Geometry makes geometric calculations and spatial reasoning accessible.