Formula
Area multiplies the sides. Perimeter walks around both pairs:
Area = length × width
Perimeter is 2 × (length + width). A trapezoid with unequal bases uses the area page.
Assumptions
- The corners are right angles.
- Length and width are the outer sides.
Worked example
A length of 8 and a width of 3 have area 24.
Input definitions
- Length
- One side of the rectangle.
- Width
- The adjacent side.
Limitations
Results are rounded for display. This is a classroom calculation, not a measurement from a lab or a financial filing.
Questions
What if length and width are equal?
The shape is a square, and the same formulas apply.
Where is the volume?
Add a height on the volume calculator. That page is a box, not a flat rectangle.