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Rectangle calculator
Calculate area, perimeter and diagonal from width and height.
Numbers and dates
Text
Browser only
Runs locally in your browser. Your files, pasted content and generated output are not uploaded. Reset clears this tool’s working data.
This tool needs JavaScript. If it does not load, refresh the page and try again.
How to use this tool
- Enter values using decimal points and choose the operation or assumptions shown.
- Select Calculate and review the numerical result and its stated conventions.
- Download the result or amortization schedule when available. Reset restores the example inputs.
Examples
A 3 by 4 rectangle has area 12, perimeter 14 and diagonal 5.
Limitations
- Runs locally. Decimal calculations use floating-point arithmetic, rounded to 12 significant digits; monetary displays use two decimals. Exact integer and fraction results are labelled separately.
- All dimensions must use the same length unit, from 1e-12 to 1e12. Area and volume use the square or cube of that unit.
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