Mathematics · Geometry
Rectangle Calculator
Calculate area, perimeter and diagonal from length and width.
Inputs and results stay in this browser. Change one value at a time to explore the relationship.
Calculation steps
- Area = 10 × 6 = 60.
- Perimeter = 2(10 + 6) = 32.
- Diagonal = √(10² + 6²) = 11.6619037896906.
Definition and formula
Area measures the enclosed surface, perimeter measures the boundary and the diagonal follows the Pythagorean theorem.
Area = length × width; perimeter = 2(length + width)
Worked example
A 10 by 6 rectangle has area 60, perimeter 32 and diagonal ≈ 11.66.
Common mistake
Use consistent units for both dimensions before calculating.
How to learn with this calculator
Begin with the worked example, then change one value while keeping the others fixed. Compare the new result and calculation steps to identify which part of the formula changed.
Clear answers
Frequently asked questions
What does the Rectangle do?
Calculate area, perimeter and diagonal from length and width.
How does the Rectangle work?
The calculator applies Area = length × width; perimeter = 2(length + width). Area measures the enclosed surface, perimeter measures the boundary and the diagonal follows the Pythagorean theorem.
What can I learn from the Rectangle?
It connects the mathematical rule to your chosen numbers and shows each calculation step. Change one input at a time to see how the result responds.
Does MW SysArc receive or store what I enter?
No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.
How should I use the result?
Use the steps to understand the method, then verify important school or professional work using the notation and rounding rules required in your setting.
Last reviewed 2026-07-14. Calculations tested 2026-07-14.