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THE FEUTEX TOOLKIT

Rounded Rectangle Outline and Area

Calculate area and perimeter for a rectangle with four equal circular corner fillets.

Geometry workspace● Runs in your browser
01 Your input
02 Your result
View or copy raw result data
FormulaArea = w*h-(4-PI)*r**2; Perimeter = 2*(w+h)-8*r+2*PI*r
Sources and model references

Made for real tasks

  • Calculate area and perimeter for a rectangle with four equal circular corner fillets.
Explore step-by-step workflows →

Worked example

Inputs

Width
20 length
Height
10 length
Corner radius
2 length

Expected results

Area
196.5663706 length²
Perimeter
56.56637061 length

Load the example in the workspace to reproduce these results. Display rounding does not change the underlying calculation.

How to use this tool

  1. Enter width, height, corner radius.
  2. Use the displayed units and confirm the model assumptions.
  3. Calculate and compare the outputs against your input scenario.

Try this example

{
  "w": 20,
  "h": 10,
  "r": 2
}

Accuracy and scope

Uses finite-precision arithmetic. Results describe the stated mathematical model, not measurement accuracy.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.