Perimeter of a Quadrilateral Calculator
Enter the four side lengths of any quadrilateral to get the perimeter (P = a + b + c + d) instantly — works for rectangles, parallelograms, rhombuses, trapezoids and any irregular four-sided shape.
Sum of all four sides: P = a + b + c + d
- 1
Sum of sides a and b
6 + 4 = 10 - 2
Sum of sides c and d
6 + 4 = 10 - 3
Perimeter = a + b + c + d
10 + 10 = 20
How does this calculator work?
The perimeter of any quadrilateral is P = a + b + c + d. Enter all four side lengths; the calculator adds them and identifies whether the shape is a parallelogram, rhombus, or general quadrilateral.
Formula
How this is calculated
A quadrilateral is any polygon with exactly four sides. Its perimeter is the sum of all four side lengths: P = a + b + c + d. No angles or diagonal information is needed to find the perimeter — only the lengths matter.
Special cases reduce to simpler forms: for a parallelogram or rectangle (a = c and b = d) the formula becomes P = 2(a + b); for a rhombus or square (a = b = c = d) it becomes P = 4a. This calculator detects these special cases by comparing opposite sides and labels the shape accordingly.
Note that the perimeter alone does not uniquely determine the shape. You can form many different-looking quadrilaterals with the same four side lengths simply by varying the angles. If you need the area, additional information (angles, a diagonal, or vertex coordinates) is required — separate calculators handle rectangles, parallelograms, and trapezoids specifically.
Frequently asked questions
A quadrilateral is any closed, flat shape with exactly four straight sides. Common types include rectangles, squares, parallelograms, rhombuses, trapezoids, and irregular four-sided polygons.
No. Perimeter depends only on side lengths, not angles. Angles are needed to compute the area of a general quadrilateral.
If a = c and b = d the shape is a parallelogram (or rectangle if it also has right angles), and the perimeter simplifies to 2(a + b). If all four sides are equal it is a rhombus (or square) with perimeter 4a.
Also known as
TG we-Calculate Editorial Team. (2026). Perimeter of a Quadrilateral Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/perimeter-quadrilateral-calculator
TG we-Calculate Editorial Team. "Perimeter of a Quadrilateral Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/perimeter-quadrilateral-calculator.
TG we-Calculate Editorial Team, "Perimeter of a Quadrilateral Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/perimeter-quadrilateral-calculator
@misc{wecalculate_perimeter_quadrilateral_calculator, title = {Perimeter of a Quadrilateral Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/perimeter-quadrilateral-calculator}}, year = {2026}, note = {TG we-Calculate} }
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