The technology of fish finders has transformed the sport of fishing. The best fish finders moved fishing from trying to detect an ideal spot to cast a line by a hunch, into a science of locating both fish-friendly objects underwater as well as the actual sea life itself.
With fish finders, you can now troll around in your boat, check the map, and spot the perfect location to drop a line, or pick up images of game fish right underneath or next to your vessel.
With all this technology, and a variety of brands, how are you supposed to pick the best fish finders, though? Once you select one, how are you supposed to figure out what you are looking at if it’s your first time using one? Particularly with SideScan, the image can be a bit confusing, and you might feel as if you supposed to decipher a somewhat alien, double-sided medical ultrasound.
You can breathe a sigh of relief—these devices are actually more straightforward to understand that you might expect. Once you know what you’re looking at, these units can make fishing a whole lot more successful and enjoyable. There are a lot of fish finders available.
We took a look at seven of the best fish finders on the market right now.
Garmin fish finders can be excellent options for those who fish as a hobby and want relatively inexpensive equipment. As a company that used to be known for GPS devices, you can bet that their fish finders are fantastic when it comes to mapping and global positioning.
With the Striker 4, you can mark your favorite locations, note fish hot spots, and utilize the GPS for docking information, as well. The sonar history function allows you to check back over areas you already passed to see if you might have missed an area with potential activity.
This Garmin fish finder has a built-in swivel mount and a 3.5-inch color display. The sonar on the Striker 4 can read at a max water depth of 1,600 feet in freshwater and up to 750 feet in saltwater. If needed, it can be enhanced with a CHIRP GT8 or GT15 transducer for improved performance, sold as a separate option.
The Striker 4 also has a built-in flasher, making it ideal for ice fishing. One of the things we like most about this unit is the straightforward, keyed interface.
It doesn’t take a huge learning curve to figure out your way around this device, and it is not a smart screen with too many functions to handle. The simple, compact, easy to use quality of this fish finder makes it a winner for the casual angler who wants to spend under $150.
The Garmin echoMAP is a fish finder that bridges the affordable to a mid-range price point. This unit has a built-in 500 CHIRP standard sonar as well as a CHIRP “ClearVü” sonar for imaging. The display screen is just over 3.5 inches (5 inches diagonal), so it is on the small side for hobbyist anglers.
The Garmin echoMAP comes with the option of “U.S. BlueChart g2 charts, U.S. LakeVü HD maps, and Canada LakeVü HD” as separate purchases to further customizer your device. The ease of use with this GPS-focused fish finder is one of the selling points. Garmin’s Quickdraw Contours software is included, and this feature allows you to craft your own customized maps in one-foot contour segments as you go.
Installation is straightforward with the corded mount. You can just plug it in, set up, and go. Garmin also offers a trolling or transom motor mounting option in the box. The transducer is a mid-band CHIRP, and the unit comes loaded with BlueChart maps for the United States coast.
If you are looking for a fish finder that is particularly easy to install and can be read simply even in direct sunlight, this is an option to consider. It is worth noting this is a unit more designed for saltwater, and the maps are focused on the coastal regions. If you are fishing on lakes, especially smaller ones, you may find there are no charts for your location loaded on the device.
The HOOK2 5 is a Lowrance fish finder with a five-inch display and auto-tuning sonar. For anglers who want to spend less time fiddling with the settings menu, this unit is worth checking out. This device would have been fantastic when I was on the family pontoon at a cabin lake.
It has a CHIRP sonar cone, like many fish finders, but it is pre-loaded with the United States inland lakes, making it an excellent option for freshwater fishers. One of the things we like most about this unit is the detail on the thousands of freshwater lakes. You can actually search for active fish areas, underwater structures, and geographical changes. This takes a lot of the tedious legwork out for you.
At this price point, options start to open up with the various displays. This Lowrance fish finder has DownScan, SideScan, and the CHIRP sonar, which shows those fish arches clearly. The SD card slot allows you to add in upgraded maps aftermarket and continue to update your information as new charts are released.
The Solarmax display makes this fish finder easy to see in direct sunlight. On the screen, you can do TripleShot, with three different views on your display for more precise underwater reading.
The Garmin Striker Plus 7Cv with Cv20-TM transducer is a mid-range priced fish finder that focuses on Garmin’s “ClearVü” imaging. This unit does not have SideScan, but the display of the sonar is excellent, and the GPS works phenomenally.
Not only is this brilliant at picking up imaging for fish, but the GPS marks your location and works well in navigating around a lake or offshore.
We like the easy install of this device and the water-resistant display. You can also store information and one-foot contours for up to 2 million acres—plenty of coverage to note down sweet spots and underwater features.
The seven-inch display is a bit bigger than the Lowrance Hook2 5 for virtually the same price, so if the screen size matters to you, this might be worth considering. Another perk to Striker Plus 7cv is the built-in Wi-Fi and accessibility to the ActiveCaptin™ app. With the app, you can get smart notifications and community data for more up-to-date use on your fish finder.
The imaging is one of the best parts of this fish finder. The display has nearly photographic quality, and the fish arches are clear and distinct. With 2D sonar (200 kHz) it has a depth of 2,300 feet, and with the ClearVü (455 kHz) it goes as far as 250 feet—ample depth for many offshore fishing situations.
Hummingbird fish finders are a notable brand on the market, and the PIRANHAMAX 4.3 DI is an example of why they are popular. This somewhat compact, reasonably priced unit focuses on down imaging.
You get a super accurate display of what is under your vessel on a 4.3-inch display that can be turned 180 degrees, depending on your preference.
The fish alarm option is a cool feature, allowing you to take your eyes off the screen more often. With a simple hookup to your motor battery, it runs on 12 volts, and installation is a breeze.
The compact unit is easy to take with you and to connect on a small boat, a pontoon, or even a kayak (with a separate battery). It has a fixed mount to help hold it in place even on rocky waters.
The PIRANHAMAX has 480 x 272 resolution and a depth capacity of 320 feet with down imaging and 600 feet sonar. For some of the more serious, deep water anglers out there, the depth might be on the shallow side.
For most casual fishers, we found this to work wonderfully, though.
Take note, this unit does not have GPS or SideScan. So, do not depend on this fish finder to help you navigate back home or search off the sides of your boat for fish activity.
However, if you just want a super clear image of what is below you, and you have another navigation system or are on a small lake, this unit can be fantastic.
Lowrance fish finders are popular on the market partially because of units like this model. The ample nine-inch color display on the HDS-9 Live has both 3D and “active imaging” sonar.
The various split-screen options allow you to see HD images of not only fish but also potential hot spots with their StructureScan feature.
You also get smartphone integration with the HDS-9 Live, which allows alerts such as texts or calls to show up on the display so you can focus on fishing instead of on checking a phone. Additionally, it has GPS with a 10Hz location update for accuracy.
This price point on this device is higher than some, but with that, you get SideScan, DownScan, StructureScan, and TotalScan all with HD photographic quality.
It is equipped with CHIRP sonar and pre-loaded coastal maps. Aftermarket navionics maps are also available for those who want the full spectrum, including topography.
One of our favorite features is the quick routing, which can show you the fastest and safest ways around potential hazards, measuring your boat’s draft, beam, and height.
With “RealVision” 3D CHIRP sonar, SideScan, and traditional sonar, the Raymarine Axiom 7 is an advanced fish finder for tech-loving anglers.
The super rapid display comes from a quad-core processor and works consistently without much if any lags.
You also get built-in Wi-Fi and Raymarine apps at no extra cost so you can actually control the unit from your smartphone.
This device is for both saltwater and freshwater fishers alike, with over 20,000 pre-loaded charts, including navionics for those who want topography in their display for the full picture of where they are casting their line. A depth finder, GPS, and plotter are built-in for navigation and charting ideal fishing spots.
A unique feature is a gyro-stabilized sonar to compensate for boat movement. The Axiom 7 has a port for ethernet, 12 volt DC power with NMEA2000 connectivity, a USB port for remote card readers and charging smartphones, and the sonar transducer slot.
We like this fish finder for those who are particularly into tech, smart devices and want a variety of views in their unit.
These devices work by way of sonar and CHIRP. The sonar operates via an electronic pulse that gets sent out to something called a transducer.
This transducer then translates that initial pulse into sound waves. The sound waves are sent through the line of water, and the wave moves down, being stopped by entities beneath the surface. Once the sounds wave hits an object, it rebounds back up to the transducer.
The objects the sound wave picks up will not only be the seafloor, seaweed, and rocks, but also those sought after fish—both bait and game. You then get a relatively detailed picture (especially with down imaging) on your screen.
New fish finders can not only show you the lake or ocean floor and areas of fish. The newer technology in these devices can also provide an array of helpful information.
Your modern fish finder will usually tell you the depth of the seabed, the distance your sonar range is set to, the temperature of the water, and they will also be outfitted with GPS to help you navigate in larger bodies of water.
Some have Navionics or topographic mapping, as well.
Traditional sonar works by sending out a “ping” of energy, or type of pulse that shoots down through the water. The device then listens, in a sense, to the echo of that pulse returning.
That information is processed and translated onto the display screen, somewhat like a bat’s echolocation.
CHIRP, which stands for Compressed High-Intensity Radiated Pulse, has entirely altered the game with fish finders. CHIRP was initially utilized by the military but made its way into civilian devices such as fish finders around 2009.
CHIRP sends out a longer pulse that that of old school sonar. This pulse emits quite a bit more energy into the aquatic column. This energy has a broader frequency range than traditional, up to that of 117kHz. The pulse itself is different, too.
Traditional sonar emits the ping, but CHIRP sends out a sweep in a variety of frequencies. The transducer that comes with your fish finder begins a low vibration, moving up to a high frequency. CHIRP units put out roughly 10 to 50 times more energy than traditional sonar. For you, this results in more detailed images with greater accuracy, as the device can pick up more.
If you have never used a fish finder, you might find yourself feeling like it is an easy way out or halfway cheating.
Sure, they can make getting a big catch much more comfortable, but just because its new technology does not mean it is wrong to use it. Fishing without a finder requires using your senses to scout out the best areas and spots fish are most likely to congregate.
Additionally, fish finders can be helpful in remembering locations you’ve had good luck in fishing, they can keep you from getting lost with GPS, and they can help keep you connected to your loved ones with smartphone capabilities.
These functions can be turned off, but if you need to be on call for specific situations, they can free you up to go fishing when you might otherwise need to stand on land. Some imaging can also prevent you from boating over a dangerous structure that could damage your vessel, too.
These days, there are so many different brands, types, and price points for the best fish finders.
Every person will have different needs, depending on the sort of fishing you are doing, what kind of maps you want, and whether you need something that can handle deep-sea fishing. Consider some of the following when looking at fish finders:
You might want to be able to overlay two maps side-by-side. In some units, you will have the option to have SideScan on one side, and the function to overlay new images you pick up onto your map.
Many will not keep this new mapping forever, but long enough for you to mark objects such as pipes, seaweed beds, ledges, and drop-offs, so you do not have to relearn the area over and over if you fish it frequently.
The energy source of your sonar fish finder is read in Watts. As you might expect, the higher your wattage, the more potential your device will have, and the more efficient and even detailed it can be.
With less power, your readouts will be more delayed. That means you might have to circle back around if your picture of the area your boat travels over displays slower.
The upside of this can be the cost. If you are a weekend warrior with fishing and do not depend on it to make a living, a slower, less powerful fish finder could work just fine for you.
On the lowest end of the spectrum, you will need at least 800 Watts for a fish finder. The general recommendation for the typical angler would be roughly 3,000 Watts or more.
The deeper the water, the more power you will need. So, if you only fish on a small lake as a hobby, a more affordable, lower wattage device should be excellent.
If you are heading out to do deep-sea fishing or on the Great Lakes, you will need a higher power unit.
Your price point will make a significant difference in the type of fish finder you select. Some fish finders are as low as roughly $100 while others cost well over $1,000.
Deciding your fish finder budget before you make a purchase is a wise decision, as an impulse buy of the fanciest gadgets out there can set you back several hundred dollars or more.
In the past, 2D sonar was the only way to view fish with even the best fish finders. The problem with 2D sonar is the limited space around the boat that the image picks up. You were pretty much stuck with the view directly below the sonar gear.
However, with the advent of downing imaging and “SideScan,” you could now see below your boat in the more traditional method, as well as off to the sides with this newer technology. Using both helps you cover a lot more ground and detect fish both below your vessel as well as sea life off to the sides. This technology can take your view from a few dozen few wide, to an image cast of over 200 feet wide.
Obviously, having a wider net of view, so to speak will help you map more area faster. It can also help you pick up rocky areas or fallen timber you might have missed with only a 2D sonar model. Some of the best fish finders will provide a shot of both 2D sonar and SideScan on display side-by-side.
This option is the best of both worlds, helping you see what is below your boat as well as along the sides. It can also aid you in detecting what exactly you are seeing while you are first getting used to the feel of deciphering the images.
In addition to down imaging providing a more extensive range with SideScan, it also offers more detail than traditional sonar. If you compare the same shot of a lake or seafloor next to each other, the sonar can provide a general layout of the bottom and will show colors such as red to indicate how hard or dense the seabed is below you.
Sometimes you will see spots that are challenging to tell if they are trees, rocks, fish, or other objects. The down imaging will provide greater detail to help you identify the entities below.
With some newer technology, you will get a display that can initially be confusing, especially in the case of “SideScan” with a transducer fish finder. In some fish or depth finders, you will see a bright line down the middle, with dark areas on either side and then lighter sides.
These lighter sides can look somewhat like the bottom of the lake or ocean, and you would be correct about that.
When you get a display like this, it can be a little difficult to understand at first, but essentially, you are looking at both the left and right side just under your boat, the black or dark areas are the water between the boat bottom and the lake or seafloor.
Once you get a feel for reading these displays, you will better be able to interpret what you see on the bottom of the lake.
Sometimes other dark areas will show up on the far right or left (on the ocean or lake floor), and this can indicate a shadow of an overhang, ledge, or especially deep drop off underwater. A particularly bright area on the lake or ocean floor will usually show a hard or rocky area. These spots can be ideal for finding fish, as they can hold heat in colder months, or they can display rocky, coral areas where fish like to hide.
In some lakes, you might find little patches of tiny crater-like areas on your SideScan view. In some regions, these can indicate bluegill beds. In summer, bluegill will spawn, and larger fish such as bass will circle the area to feed on the bluegill. If you see these small patches of numerous small, crater type spots, mark them on your map, and you can revisit them to fish later.
When you use a “DownScan,” it can be a little easier to understand when first utilizing more advanced equipment. Transducer scanners look similar to an ultrasound picture. The SideScan might appear confusing to a first-time user.
The DownScan is more straightforward, showing what is below your scanner with the black area being the water, and the lighter region that of the seabed. In this view, you will also be able to see areas of brush or fallen trees, rockier elevation, or coral outcroppings.
In 2D sonar, you will often see a color display with a line across the screen. This line indicates the bottom of the lake or ocean, and the space above it is the water between your boat and the seabed. Areas in the line, or seafloor, can show fallen brush or trees, jutting rocks, or other debris underwater.
When the color line of the bottom itself is thicker red, it generally means that it is a harder area, such as firm bottom or rock. The red will be fainter in softer spots on the seafloor.
Occasionally, when looking at 2D sonar, when you run into rocky or hard bottom areas, you will see a type of “echo” on your display, such as another colored line on the read below a thick red reading. That means the transducing has pinged twice, indicating hard or rocky floor.
Again, sometimes this is an ideal area to look closer for fish.
What you want to look for on your fish finder are independently floating lighter spots in the water section of your mapping, or one or several arch shapes. If you see an arch of a bright spot or color on a 2D scanner, this shows where a fish just moved, often a game fish.
A dot in the water that appears to hover could be a fish, but depending on the area, it may not be biting.
If you see these hovering spots in the “shadow” of a ledge or drop off, the fish might be resting or suspended in that area, but potentially inactive and not scavenging for food moment. When many fish are actively feeding, they will be up on top of ledges or ridges. The arches are moving fish, generally larger in size, and these can also be ideal spots to set a line.
You might also see a school of fish as several small points in the middle of the water section on your map. Generally speaking, in the water areas of your view, whether it’s the black area on a transducer, or the white area indicating water on a 2D sonar, you want to seek out arches or small hovering dots.
These are the fish, and even if they are small, this is what you will be searching for.
Spotting areas that look almost like hair in the floor can often indicate brush piles, seaweed, or fallen trees. These are another area to check for fish spots in or around these piles or beds of seaweed because this type of place will provide fish with some hiding spots, but more importantly, food.
It is crucial to drive your boat at the correct speed when utilizing a fish finder. If your pace is too slow, the image can become blurry, and if you go too fast, the wake of your boat can disturb the transducer, and it may not pick up the pictures you are looking for.
Generally, driving your boat around three to four miles per hour is ideal for many fish finders.
You can change the sensitivity in most modern fish finders. This feature can be helpful when moving from an area with a rockier bottom to a softer, muddier surface and vice versa.
Considering hard seafloor will show up brighter, you can turn the sensitivity down a bit to dim the intense brightness of your SideScan or DownScan view.
With softer floors, you can adjust it up a bit to provide more contrast between the water or seabed. Doing this will also help images such as rotten logs or other debris show a little more clearly.
Turning up the contrast will give you a sharper image but will create more of a difference between the light and dark areas. Some smaller details, like small debris, can get lost in the imaging if the contrast is turned up too much. With lower contrast, the image will be hazier, but smaller items can sometimes show up easier.
The range is how far away from your boat your image catches. The best fish finder will detect the water below your boat in a cone shape, starting with the point of the cone at the equipment, and the image spreading as it travels downward.
If you set your range to 90 feet, for example, it will pick up imagery for 90 feet in either direction of your boat.
Putting out a more extensive range can be helpful for initial mapping of an area to detect fallen trees or rocky outcroppings. Setting your scope to a tighter area can be more precise for picking up smaller fish when it’s time to cast your line.
In 2D sonar, the range will typically be set to auto, and automatically adjusts depending on the depth of the water. If you want to get a more accurate picture of what kind of seafloor is under you, consider changing the range off of auto and setting it to roughly double the depth of water you are fishing in.
For example, if you are fishing in 30-foot water, you can set it to 60 feet. Having a deeper range than the water might seem unnecessary. However, when you do this with 2D sonar, you can pick up that “double ping” on the sonar indicating especially hard bottom seafloor.
Again, in hard areas or rocky floor, you can sometimes have better luck finding fish. So, setting your range depth to double your water depth might help you pick up the areas of seabed you are more likely to find fish.
On some units, such as Hummingbird Fish Finders, you can turn sharpness on and off, or adjust it between high, medium, and low. Make sure you have the sharpness turned on.
Otherwise the picture will usually be poor quality. Many people find that the medium setting works best for them, to prevent haziness, but also avoid being over pixelated.
The Garmin Striker 4 does the job for most casual anglers, measures helpful information such as water temperature, has a clear enough screen, and most importantly, is extremely affordable. We also like the straightforward keypad on that device.
The Lowrance HDS-9 Live is a lot more money, and definitely for those who are more serious about fishing. However, the array of features of and capabilities make it one to check into if you want an accurate, detailed fish finder.
Whether you are on an inland lake or river, fishing the Great Lakes, or taking your boat offshore on the ocean, a fish finder can be an incredible asset.
The GPS that is on many of these units can be a lifesaver in navigating your way back, especially out in open water or after dark, and makes the act of fishing far more enjoyable when you can return to hot spots of sea life and bring in catch after catch. For those who make a living fishing, these can feel like an absolute necessity.
So, take it from the pros. Try one out (check for a return policy if you are unsure about it) and see the kind of difference it makes in your fishing game. You can always start with a lower-priced model, and if you love it, eventually move up to the more advanced, various split-screen units.
Even with the most basic setup, we think fish finders can make a day on the water more enjoyable, less stressful, and certainly more abundant when it comes to your catches.