Drag the vertices to reshape any polygon. Watch the angles and perimeter update live. Discover shape properties!
The interior angles of any triangle always add up to 180Ā°. For any quadrilateral it's 360Ā°. The formula for any polygon with n sides is (nā2) Ć 180Ā°.
A regular shape has all sides equal and all angles equal. An irregular shape does not. Drag the vertices to turn a regular shape into an irregular one!
This free interactive math tool helps students visualize and understand mathematical concepts. Instead of memorizing procedures, students can see how numbers work through visual models, manipulatives, and step-by-step animations. Research shows that visual learning in math leads to deeper conceptual understanding.
All math tools on SmartOnlineGames are aligned with Common Core State Standards for Mathematics and are designed for students in grades K through 8. They are completely free, require no login or account creation, and work on any device including tablets, Chromebooks, and interactive whiteboards.
Interact with the visual tool above to explore the concept. Try different inputs and observe how the output changes. Teachers can use this tool for whole-class demonstrations or independent practice. Parents can use it for homework help or math enrichment at home.
Last reviewed: April 2026