How many sides does the largest polygon have?

Answer 1

There is no mathematical limit to the number of sides that a polygon can have. As the number of sides increases the polygon will become more and more like a closed curve - a regular polygon will become like a circle. The size of the polygon and accuracy of measurement will determine when it is no longer possible to distinguish between the polygon and the curve. Nevertheless, the two shapes will be mathematically different objects.

Answer 2

A polygon can have any number of sides, but the largest named polygon is the megagon, which has 1,000,000 sides.