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WT-046
CALCULATORS / LOCAL UTILITY

Circle Calculator

Start with radius, diameter, circumference, or area and calculate all four common circle measurements with formulas shown.

GEOMETRY
LOCAL NO DATA SENT
CIRCLE WORKBENCHRADIUS / DIAMETER / CIRCUMFERENCE / AREA
KNOWN MEASUREMENTSTART WITH ANY ONE VALUE
π is used at full browser precision; displayed answers are rounded only for readability.
RADIUS
DIAMETER
CIRCUMFERENCE
AREA
DIAMETERd = 2r
CIRCUMFERENCEC = 2πr = πd
AREAA = πr²
STEPSFIND RADIUS → DERIVE EVERYTHING ELSE
READYChoose a known circle measurement.

LOCAL TOOL: Circle measurements are calculated entirely in your browser.

FIELD NOTE / 046

Once you know the radius, every common circle measurement follows from it.

The diameter is twice the radius, circumference measures the distance around the circle, and area measures the space inside it.