Geometry Tool

Plane Geometry Reference

Quick reference for 2D shape areas and perimeters.

Square

AreaA = a²
Perimeter / CircumferenceP = 4a

Where 'a' is the side length.

Rectangle

AreaA = lw
Perimeter / CircumferenceP = 2(l + w)

Length 'l' and Width 'w'.

Circle

AreaA = πr²
Perimeter / CircumferenceC = 2πr

Where 'r' is the radius.

Triangle

AreaA = 1/2 bh
Perimeter / CircumferenceP = a + b + c

Base 'b' and Height 'h'.

Parallelogram

AreaA = bh
Perimeter / CircumferenceP = 2(a + b)

Base 'b' and Height 'h'.

Trapezoid

AreaA = 1/2 (a+b)h
Perimeter / CircumferenceP = a + b + c + d

Parallel sides 'a' and 'b'.

Ellipse

AreaA = πab
Perimeter / CircumferenceP ≈ π(3(a+b) - √((3a+b)(a+3b)))

Semi-major 'a' and semi-minor 'b'.

Regular Polygon

AreaA = 1/2 n s a
Perimeter / CircumferenceP = n s

n sides, length s, apothem a.

Geometry is the foundation of all design.

# About This Calculator

Plane Geometry deals with flat shapes like lines, circles, and triangles—shapes that can be drawn on a piece of paper.

This guide lists the formulas for **Area** (space covered) and **Perimeter** (distance around) for the most frequent 2D shapes.

Frequently Asked Questions

Is Plane Geometry Reference free to use?+

Yes, Plane Geometry Reference on Matheric is completely free to use. We believe in accessible education and utility for everyone.

How accurate is Plane Geometry Reference?+

We use standard mathematical formulas and high-precision computing algorithms to ensure results for Plane Geometry Reference are accurate for academic and professional use.

Can I use Plane Geometry Reference on my phone?+

Yes! Plane Geometry Reference is fully responsive and optimized for all devices, including smartphones, tablets, and desktops.

Do you save my data?+

No. We prioritize your privacy. All calculations are performed in your browser or temporarily processed, and we do not store your personal input data.

How do I report a bug?+

If you notice any issues with Plane Geometry Reference or have suggestions for improvement, please contact us via the link in the footer. We value your feedback!

Can I request a new feature?+

Absolutely. We are constantly expanding our toolset. Feel free to reach out with your requests, and we might build it next!

About

Plane Geometry deals with flat shapes like lines, circles, and triangles—shapes that can be drawn on a piece of paper.

This guide lists the formulas for **Area** (space covered) and **Perimeter** (distance around) for the most frequent 2D shapes.

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