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Calcimator

Circle Calculator

Calculate radius, diameter, circumference, area, sector area, and arc length of a circle from any known value.

Inputs

°

Results

Area

78.54

Circumference31.42
Radius5
Diameter10
Sector Area78.54
Arc Length31.42

Area

78.54

How to Use This Calculator
  1. Start by filling in the input fields below. Results update instantly as you type, so you can experiment with different values to see how they affect the outcome.
  2. Known Value — Calculation mode to use. Choose from: Radius, Diameter, Circumference, Area. default: 0.
  3. Value — The input value. Accepts values from 0 to 100,000 (default: 5).
  4. Sector Angle (degrees) — enter a number in °. Accepts values from 0 ° to 360 ° (default: 360 °).
  5. Once all inputs are set, review your results in the Results panel. Here's what each output means:
  6. Area — shown as a numeric value. This is the primary result of this calculator.
  7. Circumference — shown as a numeric value.
  8. Radius — shown as a numeric value.
  9. Diameter — shown as a numeric value.
  10. Sector Area — shown as a numeric value.
  11. Arc Length — shown as a numeric value.
  12. View the Sector Breakdown below for a visual breakdown of how the numbers relate to each other.
  13. Explore the related calculators below if you need deeper analysis or want to approach this topic from a different angle.
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Formula

A = πr², C = 2πr

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