Free Rectangle Calculator

Calculate rectangle area, perimeter and diagonal.

Rectangle Calculator

Enter a value to begin.

How to use this rectangle calculator

  1. Enter the two side lengths.
  2. Check the inputs and preview, then use the primary action.
  3. Download, copy or use the result shown by the tool.

How the result is calculated

Area is length × width, perimeter is twice their sum, and the diagonal follows Pythagoras.

All calculation and transformation work happens in this browser tab. No entered value is sent to an Noler Tools application server.

Important limitations

Results are provided for convenience and should be checked independently before an important decision. A format or checksum result never authenticates an identity, document, account, licence, vehicle or registration.

Frequently asked questions

Is this rectangle calculator free?

Yes. It is free to use and does not require an account.

Does Noler Tools save my input?

No. The input and result remain in temporary browser memory and are not uploaded or saved by this site.

Related tools