Google Maps has no boat directions and no nautical chart data. Its directions cover driving, public transit, walking, ride sharing, cycling, flights and motorcycles, and its map layers show roads, satellite pictures, terrain and traffic, not water depths or buoys. It is still handy for looking over a marina in satellite view or measuring a straight line in miles. For a trip by boat, measure the distance over water in nautical miles with our Sea Distance Calculator and check the route on a nautical chart.
What Google Maps Can Do for Boaters
- Measure a distance. On a computer, right-click your starting point, choose Measure distance and click the map to add points along your path; on a phone, touch and hold the map, choose Measure distance and add points. The total is shown in miles and kilometers.
- Show satellite pictures. In Layers, the Satellite map type shows aerial pictures, useful for looking over a marina, a launch ramp or a shoreline before you go.
- Show coordinates. On a computer, right-click a spot on the map and its latitude and longitude appear at the top of the pop-up in decimal degrees; click them to copy. Our Latitude and Longitude Converter turns them into degrees and minutes for a chart plotter.
- Export a map you made. In Google My Maps, a map you draw yourself can be exported as a KML or KMZ file (Menu, then Export to KML/KMZ); the KML to GPX Converter turns it into a GPX file for apps that read GPX.
- Get you to the boat. Driving directions take you to the marina or the ramp like any other trip on land.
What Google Maps Can’t Do on the Water
- No boat directions. Google’s help page lists directions for driving, public transit, walking, ride sharing, cycling, flight and motorcycle. Boating isn’t one of them, and driving routes are designed for cars.
- No depths, buoys or hazards. The map types and layers in Google’s help are the map, satellite, terrain, traffic, transit, biking, Street View, globe view, air quality, travel time and wildfires. None of them shows soundings, aids to navigation or chart notes.
- No nautical miles. The measuring tool gives miles and kilometers, while boaters and charts work in nautical miles and knots.
- Straight lines, not routes over water. The tool measures straight lines between the points you add; Google’s own example is the mileage in a straight line between two cities. A boat has to go around land and shallow water, so the route over water is usually longer.
A nautical chart is a different kind of document. It shows water depths, the shoreline, tide predictions, obstructions such as rocks and wrecks, and aids to navigation, NOAA explains, while a map shows landforms and routes such as roads. The Coast Guard’s rules for aids to navigation add that this information “cannot be obtained from other sources, even ones such as topographic maps, aeronautical charts, or atlases” (33 CFR 62.21).
How to Measure Distance on Water in Nautical Miles
Use a map that routes over water. In the Sea Distance Calculator, tap the water or search more than 5,000 ports and marinas worldwide. It measures a computed route over water, not a straight line, and shows it in nautical miles, statute miles and kilometers; add your cruising speed and fuel use for the trip time and fuel. It is a planning estimate, not a charted navigation track.
Convert a Google Maps measurement. Multiply statute miles by 0.869, or divide kilometers by 1.852, to get nautical miles: 30 miles is about 26.1 nautical miles. The Miles to Nautical Miles Converter does it for you. It is still a straight-line distance.
Measure on a nautical chart. Open a pair of dividers between two points and read them on the latitude scale at the side of the chart: one minute of latitude is one nautical mile. Our guide How to Read a Nautical Chart shows how.
Google Maps distances in nautical miles:
| Statute miles | Kilometers | Nautical miles |
|---|---|---|
| 1 | 1.6 | 0.87 |
| 5 | 8 | 4.3 |
| 10 | 16.1 | 8.7 |
| 25 | 40.2 | 21.7 |
| 50 | 80.5 | 43.4 |
| 100 | 160.9 | 86.9 |
A statute mile is exactly 1,609.344 meters and a nautical mile exactly 1,852 meters, so one statute mile is about 0.869 nautical mile.
Boat Travel Time and Fuel
Distance is only part of a trip plan. The Boat Travel Time Calculator takes a departure and a destination on the map, or a distance you already know, and shows the time underway at your cruising speed in knots; it adds no time for stops. For popular Florida Keys and Bahamas trips, our Boat Routes pages give the distance, time and fuel ready-made.
Free Nautical Charts From NOAA
For navigation, use a nautical chart. NOAA’s electronic navigational charts (ENCs) are free to download from Coast Survey, and recreational boaters use them in chart plotters and other electronic chart systems:
- The NOAA ENC Viewer shows the charts in a web browser.
- The NOAA Chart Locator downloads them.
- NOAA Custom Chart makes a printable PDF chart from the latest ENC data, with depths in meters, feet or fathoms.
- For many U.S. rivers, the U.S. Army Corps of Engineers publishes Inland ENCs.
Frequently Asked Questions
Does Google Maps have boat directions?
No. Google’s help page lists directions for driving, public transit, walking, ride sharing, cycling, flights and motorcycles; boating isn’t one of them.
Can Google Maps show water depth?
No. Its map types and layers, such as satellite, terrain, traffic and transit, don’t show depths, buoys or hazards. Depths are on nautical charts, such as NOAA’s free electronic navigational charts.
How do I measure distance on water with Google Maps?
On a computer, right-click the starting point, choose Measure distance and click to add points along your path; on a phone, touch and hold the map first. The total is in miles and kilometers, and it is a straight-line distance.
How do I convert Google Maps miles to nautical miles?
Multiply the statute miles by 0.869, or divide the kilometers by 1.852. For example, 30 miles is about 26.1 nautical miles.
What can I use instead of Google Maps for a boat trip?
For distance, time and fuel, a calculator that routes over water, such as our Sea Distance and Boat Travel Time calculators. For navigation, a nautical chart, such as NOAA’s free ENCs in a chart plotter or a printed NOAA Custom Chart.
Is a Google Maps distance the same as the distance by boat?
Usually not. The measuring tool draws straight lines between the points you add, while a boat has to go around land and shallow water, so the route over water is usually longer.
Sources
- Google Maps Help, Get directions and show routes, Measure distance between points and Use layers (read Oct 19, 2026), and Search by latitude & longitude in Google Maps (read Oct 21, 2026).
- Google My Maps Help, Share, download, or print your map (read Oct 21, 2026).
- NOAA National Ocean Service, What’s the difference between a nautical chart and a map? (updated Sep 23, 2026; read Oct 19, 2026).
- NOAA Office of Coast Survey, NOAA ENC and NOAA Custom Charts (read Oct 19, 2026).
- 33 CFR 62.21, the U.S. Aids to Navigation System (read Oct 19, 2026).