Use this nautical calculation for a transparent unit, speed, tide, rhumb-line, or apparent-to-true wind estimate when position, heading, current, and unit conventions are explicit.

From latitude

Required number input.

From longitude

Required number input.

To latitude

Required number input.

To longitude

Required number input.

Calculate the rhumb line distance in nautical miles between two geographic positions along a constant bearing. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Distance

The resulting distance returned as a number.

• Navigation results can depend on Earth model, chart datum, magnetic variation, leeway, current, wind reference, tide station, hull form, water depth, and weather. Simplified hull-speed and rhumb-line formulas do not establish a safe passage.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Cross-check current charts, tide and weather services, vessel instruments, and approved navigation methods before operational use.

• Nautical Mile to Kilometers Converter

  Convert a distance in nautical miles to kilometers using the exact factor of one point eight five two.

• Fathoms to Meters Converter

  Convert a depth in fathoms to meters using the exact international fathom of one point eight two eight eight meters.

• Hull Speed Calculator

  Calculate the displacement hull speed in knots from the waterline length in feet.