Use this sailing calculation for planning or education when the vessel, units, reference directions, environmental conditions, and assumptions are explicitly known.

Anchor circle radius (m)

Required number in m.

The cited overview of Mooring supplies background for the terminology and domain context used by this tool.^[1]

Calculate the area a boat can sweep as a circle around its anchor from the anchor circle radius. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.

Swing circle area (m²)

Returned number in m².

• Vessel design and loading, sea state, wind, current, tide datum, weather, chart accuracy, equipment, crew, and safety margins can make real conditions differ from a simplified result.
• Use finite inputs in the displayed units, preserve source measurements and assumptions, and independently verify consequential decisions.

Cross-check current charts, tide and weather services, instrument data, vessel manuals, and applicable navigation rules, and retain a conservative alternative plan.

• Anchor Circle Radius Calculator

  Estimate the maximum anchor-to-bow radius from water depth and rode scope. Add the vessel length when checking the full area swept by the stern.

• EPIRB Satellite Footprint Radius

  Calculate the geometric horizon footprint of an EPIRB search-and-rescue satellite from its orbital altitude. Actual detection also depends on the satellite network, beacon view, and link conditions.

• Search Pattern Area

  Calculate the area swept by a square search pattern as the square of its side length.