Circle Area from Radius Reference Values

Calculate the area of a circle from radius using A = πr².

Author

Dr. Mateo Silva Herrera

Math editorial contributor

Colombian urban planner with a PhD from UCL, designing resilient infrastructure for flood-prone cities

Reviewed for accuracy by

Dr. Isabella Rossi

Math content reviewer

Italian neuroscientist at Sapienza University of Rome, studying the neural mechanisms of bilingual language processing

Last updatedFebruary 22, 2026

PublishedFebruary 22, 2026

Table of Contents

  1. All value pages
  2. Reference table
  3. FAQs
  4. Methodology and review
  5. Related conversions

Reference Value Index

This page lists 20 reference values for quick browsing and lookup.

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All Reference Values

Reference Table

Circle Area from Radius reference values
RadiusCircle Area
1 units3.1416 sq units
2 units12.5664 sq units
3 units28.2743 sq units
4 units50.2655 sq units
5 units78.5398 sq units
6 units113.0973 sq units
7 units153.938 sq units
8 units201.0619 sq units
9 units254.469 sq units
10 units314.1593 sq units
11 units380.1327 sq units
12 units452.3893 sq units
13 units530.9292 sq units
14 units615.7522 sq units
15 units706.8583 sq units
16 units804.2477 sq units
17 units907.9203 sq units
18 units1,017.876 sq units
19 units1,134.1149 sq units
20 units1,256.6371 sq units

Frequently Asked Questions

Frequently asked questions for Circle Area from Radius and its reference values.

What does the Circle Area from Radius calculator do?

It calculates finding surface coverage for circular plates, pipes, and round cutouts from the values you enter.

What formula does the Circle Area from Radius calculator use?

Area = π × radius².

What inputs are valid?

Enter a positive radius greater than zero.

When would I use this?

finding surface coverage for circular plates, pipes, and round cutouts

Methodology and Review

Each row on this page links to a value detail page derived from the same conversion data file as the main calculator and reference table. This reduces inconsistencies across page variants.

Editorial metadata and structured data are rendered across the converter page and linked value pages. Review policies are documented in our review process and editorial policy.