Should you get a Chartplotter/Fishfinder, or an MFD?

The Garmin GPSmap 840 is a chartplotter/fishfinder. And, it's also an MFD.

Quite often folks ask me the difference between a chartplotter/fishfinder, and a “real” MFD (multifunction display). Usually, the follow-up question is ‘which one do I need?”

This Garmin GPSmap 840 is a chartplotter, a fishfinder, and yes, it’s an MFD.

Let’s take each of these questions on one at a time. First off, a chartplotter/fishfinder is a unit that has both chartplotting and fishfinding functions built-in. An MFD also has both of these capabilities, but it can be expanded to act as the hub of a more advanced system. With an MFD you can add things like radar, autopilot and/or stereo control, digital gauges, camera inputs, and a whole lot more. Sometimes these units are plug-and-play, and other times you need to add black-boxes and software updates. The chartplotter/fishfinder, on the other hand, isn’t expandable (though some units do offer limited expansion abilities—their proper definition is debatable).

Which one do you need? That’s actually a pretty easy call to make. If you have a small bay boat or skiff that only requires navigational and fish-finding ability, it’s a no-brainer because you’ll never need to add things like radar or a FLIR night-vision camera. Save yourself some money, and buy a simple, self-contained unit. If you have a mid-sized boat and you’re not 100-percent sure what electronics you’ll be needing in the future, you’ll have to make a judgement call. And if yours is a large vessel (with a large budget) that you may want to add features and accessories to down the road, buying an MFD is in order.

Now, which unit should you choose? This is another question I get all the time, but it’s one I can’t answer. Different people find different menu systems better or worse, and this is very much a personal decision. You can read Shopping for the Right Fishfinder to get some ideas, and you should also check out 5 Things to Look for in a New Chartplotter. But truth be told, you’ll have to do a lot of shopping around and pressing buttons—hands-on experience is the only way to truly find out which specific unit is the best for you.