17 FOCUSED TOOLS
Quadrilateral & polygon calculators
Measure areas and outlines of rectangles, kites and regular polygons.
Choose the right calculation
A perimeter measures the outline; area measures the enclosed surface. Regular polygon tools assume equal sides and angles. For a parallelogram or trapezoid, use the height perpendicular to the selected base.
Find a tool for your question
Rectangle Area Calculator
Find the area of a rectangle from its length and width.
Rectangle Perimeter Calculator
Find the total length of the four sides of a rectangle.
Trapezoid Area Calculator
Find the area between a trapezoid’s parallel sides.
Parallelogram Area Calculator
Calculate area from the base and perpendicular height of a parallelogram.
Regular Polygon Interior Angle Calculator
Find each interior angle in a regular polygon.
Regular Polygon Area Calculator
Find the area of a regular polygon from side count and side length.
Rhombus Area Calculator
Find a rhombus area using its diagonals.
Kite Area Calculator
Find the area of a simple kite from its perpendicular diagonals.
Square Area Calculator
Find the area enclosed by a square from one side measurement.
Square Diagonal Calculator
Find the corner-to-corner distance of a square.
Square Side From Area Calculator
Recover square side length from its enclosed area.
Rhombus Perimeter Calculator
Find the perimeter of a rhombus from one side.
Regular Polygon Perimeter Calculator
Find the outline length of a regular polygon.
Polygon Diagonal Count Calculator
Count all vertex-to-vertex diagonals in a polygon.
Polygon Interior Angle Sum Calculator
Find the sum of all interior angles in a simple polygon.
Regular Polygon Exterior Angle Calculator
Find the equal exterior turning angle of a regular polygon.
Regular Polygon Apothem Calculator
Find the inradius of a regular polygon from side length and side count.
What does regular polygon mean?
It is a polygon with all sides equal and all interior angles equal.
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