About Rectangle Area Calculator
Calculate the surface area, perimeter, and diagonal length of a rectangle.. Designed for accurate, instantaneous calculations with zero wait time.
Formula
Area = Length × Width | Perimeter = 2(L + W) | Diagonal = √(L² + W²)
Example Calculation
A rectangle with length 12 and width 5 has area 60 and diagonal 13.
How to Use
- Enter your values into the form fields above.
- The calculation updates immediately in real time.
- Inspect the main summary and secondary breakdowns below.