Nautical Calculator 🛡️ 100% Client‑Side

Convert · Speed/Time/Distance · Haversine · Sailing Knowledge

Unit Converter

nm
km
mi
m

Speed · Time · Distance

kn
nm
Calculated Distance: 25.00 nm

Great‑Circle Distance (Haversine)

° ' ° '
° ' ° '
Great‑Circle Distance: 2560 nm / 4741 km

What is a nautical mile?

One nautical mile equals exactly 1,852 meters. It is based on the Earth's circumference and equals one minute of latitude.

Why 1 knot = 1 nm/hour?

A knot is defined as one nautical mile per hour. This unit is directly tied to the nautical mile, making navigation calculations intuitive.

Great‑Circle vs Rhumb Line

The great‑circle is the shortest path between two points on a sphere. A rhumb line (loxodrome) crosses all meridians at a constant angle.

📘 Nautical Navigation Explained

The nautical mile is the cornerstone of maritime navigation. This tool provides real‑time conversions, speed/time/distance calculations, and great‑circle distance estimation using the Haversine formula.

❓ Frequently Asked Questions

How many kilometers in a nautical mile?

1 nautical mile = 1.852 kilometers exactly.

What is the formula for speed, time, distance?

Distance (nm) = Speed (knots) × Time (hours). The tool automatically handles minutes.

What is the Haversine formula?

It calculates the great‑circle distance between two points on a sphere using their latitudes and longitudes.

Is my data private?

All calculations run locally in your browser. No data is ever sent to a server.