Choosing a GPS Chartplotter

Choosing a GPS chartplotter that is right for your and your vessel depends largely on how you intend to use this particular navigation tool, how much you intend to spend, where you will place the unit, and finally what other gear you plan to interface with the chartplotter.

It is all about knowing your needs as a boater and finding a chartplotter that can meet those needs. After all, who wants to spend hundreds or even thousands of dollars on the wrong product?

A number of boat electronics manufacturers including Furuno, Garmin, Raymarine, Standard Horizon, Lowrance, and Humminbird have inundated the market with chartplotters that start in price from roughly $400 and goes upwards from there into the multi-thousand dollar range.

The more expensive units have larger, high resolution color screens, more memory, and faster processors. Multi-function capability or the ability to be linked to other pieces of electronics also comes into play with the pricier gear.

Cheaper models have smaller screens, fewer features, slower processors and less memory. Still, the less expensive units are quality products that provide a helmsman with navigation information that was simply not available to the recreational boater a few years ago.

Choosing a GPS Chartplotter—Mounting Method

The GPS chartplotter must match your type of boating and agree with your budget while the physical unit itself must fit your boat. There are two main types of mounting options.

All but the largest fixed-mount displays can be bracket mounted. The bracket is usually supplied as part of the package by the maker and can be used to install the unit on the helm dash or in an overhead electronics box. With this installation, you have the freedom to mount the unit close to your line of site and to easily remove the unit when the boat is not in use. Another plus, most mounting brackets allow the unit to swivel sideways and vertically.

The second type of installation is flushing mounting the unit in the helm console. Flush mounting can be more complicated but brings a lot to the table and can be accomplished by even novice boat electronics installers. Flush mounting gives you a clean look, instant access to the unit while at the helm station, and it saves space. Many boat manufacturers install a lockable door to protect the flush-mounted chartplotter and other pieces of marine electronics from weather and thievery.

Display Screen Size Matters

Next up when choosing a GPS chartplotter is screen size. Choose a chartplotter with the largest display screen that will still fit comfortably at your chosen mounting location. With a larger screen you get more pixel which in turn offers the viewer a greater level of detail on the chart as well as additional space for other information. Screens vary from about 5 inches diagonal to 12 inches diagonal. With evolving technology, it stands to reason that the screens will get bigger, better, and cheaper—this all bodes well for marine navigators.

Screen glare used to be a downside for marine chartplotters with an LCD screen. But things have improved on this front thanks to technological advances in screen coatings and materials, such as thin-film transistor technology. Many of the lower-cost, smaller units have clear, crisp color screens. In other words, you don’t have to spend a load of money to get a chartplotter with a quality screen.

User Interface

Your marine chartplotter needs to be user friendly, look for units with high marks for user interface. Most marine chartplotters have front-mounted buttons with some high-end models having a touch screen interface or special soft keys for quick access to important functions. The hardware and pushbuttons are not as important as the actual interface programming.

Processor Power

One performance issue that can be a factor, especially when a external chart card is used, is the speed of the internal processor. Some are simply faster than others and should be a consideration when choosing a GPS chartplotter for your boat. The amount processor power a unit has will determine how fast your plotter will redraw screens as your boat moves or your range the chart. Great improvements have been made in this area in the last several years.

Navigation Accuracy

Accuracy of today’s GPS machines is better than ever and not really a significant consideration when purchasing. Most new marine chartplotters are WAAS-capable, meaning they are usually accurate to within about 10 feet.


Here’s a big consideration when choosing a GPS chartplotter. You need to ask yourself if you going to buy a standalone plotter, a multi-function plotter or a chartplotter/fishfinder combination unit? It boils down to needs, space and the size of your wallet. If you don’t fish or already have a sounder, the combo is out. But what if you want radar—or maybe you are going to want it later? Well then, a basic multi-function unit may be your choice. If you want it all in one package, which includes chartplotter, radar and a fishfinder, then the multi-function is the way to go.

More on Connectivity

If you intend to integrate your marine electronics components, then you need to become familiar with the terms, NMEA0183 and NMEA 2000. Both are simple terms referring to an interface standard that allows communication between marine electronic devices. The National Marine Electronics Association or NMEA sets the standards.

The older protocol, NMEA0183 allows the transfer of basic information between a chartplotter, marine VHF radio, and marine autopilot. Faster versions of the NMEA0183 protocol allow data transfer speeds high enough to connect an AIS system to your chartplotter.

The newest communication protocol is NMEA2000, which can also allow steering systems, engines, electrical power generation and distribution systems, fire control systems, as well as a wide variety of other gear to interface with your marine chartplotter.

As you can see, marine chartplotters for the recreational boater have come a long way and will continue to improve as technology advances.