Rectangle Calculator
Calculate rectangle area, perimeter, and diagonal.
- 100% free
- Private in browser
- No signup
- No watermarks
Result
- Area
- 60
- Perimeter
- 32
- Diagonal
- 11.6619
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About Rectangle Calculator
Rectangle Calculator on TheToolss finds the area, perimeter, and diagonal of a rectangle from its length and width using area = l×w, perimeter = 2(l+w), and diagonal = √(l²+w²). Enter both sides in any unit and get all three results at once. It is useful for rooms, screens, plots, and geometry homework. It runs in your browser — free, private, and no signup.
How to use Rectangle Calculator
- Enter the length.
- Enter the width.
- Read the area, perimeter, and diagonal.
Key features
- Area, perimeter, and diagonal
- Works in any unit
- Instant results
- Great for rooms and plots
- Private in-browser calculation
Frequently asked questions
- Is the Rectangle Calculator free?
- Yes. It is free on TheToolss with no signup.
- What formulas are used?
- Area = length × width, perimeter = 2 × (length + width), diagonal = √(length² + width²).
- Does it work for squares?
- Yes. Enter the same value for length and width to calculate a square.
- What units does it use?
- Any unit — the area is in square units and the perimeter and diagonal are in your input unit.
- Is my data uploaded?
- No. The calculation runs in your browser.
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