ScientificCalcul

Circle Area Calculator

Enter a circle radius to calculate the exact area in terms of π and a decimal approximation, with the formula A = πr² shown step by step.

Circle area calculator using radius squared times pi

Use this circle area calculator when a problem gives the radius and asks for π times the radius squared.

The result keeps π in the exact form first, then shows a decimal approximation in square units.

Learn the concept

Try these examples

  • r = 4.89
  • r = 7.6
  • r = 1.4

Quick reference

  • Circle area: A = πr².
  • If the diameter is d, then r = d/2.
  • Area units are squared, such as cm² or m².

FAQ

What is the formula for the area of a circle?

The formula is A = πr², where r is the circle radius.

Can I enter a decimal radius?

Yes. Enter the complete decimal value and the calculator will square it before multiplying by pi.

Sources and review

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