Everyday Math

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Daire Alan ve Çevre

Yarıçaptan alan ve çevre.

Data updated: 2026-08-12 Content updated: 2026-10-22
Sources

How is it calculated?

A=πr², Ç=2πr

A=πr²

Official sources

Calculation methodology Report a wrong result

Example

r=4 örneği.

Guide

Circle area (πr²) and circumference (2πr) from radius. For discs, pools, or sections. Informational only.

Circle formulae

Area = π × r²; circumference = 2 × π × r. If you have diameter, use r = diameter/2.

2026 notes and common mistakes

Entering diameter as radius doubles errors on length and quadruples area mistakes.

Tips

  • Confirm radius versus diameter input.
  • For information only—add tolerances for fabrication.

Sources: Basic geometry · Math references

FAQ

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No. Works without an account.

Official result? +

Informational only; verify official sources.

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