Fishing used to be about going to the places where you knew the fish usually would be when the time of day and the weather were right. Then you waited without knowing whether or not the fish actually were waiting for you. While you waited, you relaxed, watched the water, watched your line and pole, talked, joked, and laughed. All of that is fun, and you can still do all of that. When I go fishing, though, I want to catch fish – fish that are large enough to eat.
With a fish finder, you’ll know that the fish are there. You’ll be able to see them on the fish finder’s screen. They might or might not be biting, but at least you’ll know the school party hasn’t moved elsewhere. Below you’ll find my tips on how to find the best portable fish finder for your kind of fishing along with some fish finders that I recommend.
How Basic Fish Finders Work
Basic fish finders, sometimes called sounders, use sonar, just like ships that map the bottom of the ocean. Fish finders send a series of sound pulses into the water. They might use either ultrasonic high-frequency or high-pitched sound pulses or infrasonic low-frequency or low-pitched sound pulses.
When the sound pulses contact a solid object, they bounce back to the fish finder as an echo. The fish finder uses those echoes to create an image of the solid object.
Wide Beam or Narrow Beam
The sound pulses emerge from a basic a fish finder as either wide or narrow beams.
The wide beams are best for deeper waters. You’ll also be able to scan a wider section of the water.
Narrow beams are best for shallow waters. They show more detail than a wide beam. You’ll be able to see more distinct fish arches, underwater structures, brush and vegetation, and the contours and depressions in the bottom of the body of water.
Sonar for Basic Fish Finders
Basic fish finders use either side-scan sonar or down-scan sonar.
Side-scan sonar sends sound pulses out to the side and returns a side view of the objects that return echoes. The sound pulses can travel as far as 240 feet to each side.
Down-scan sonar sends sound pulses down into the water and returns a top-side view of the lake, river, or stream bed and of the objects on and above it.
More Advanced Fish Finders and What They Do
More advanced fish finders may transmit sound pulses across a range of frequencies (CHIRP sonar), use combinations of wide and narrow beams, and use side-scan and down-scan sonar to capture more detailed images.
Regular Sonar Versus CHIRP Sonar
The regular sonar used in basic fish finders sends out sound pulses at a single frequency. CHIRP sonar sends out the sound pulses over a range of frequencies. It analyses the differences in how the echoes return at each frequency to create a clearer, more distinct image on the view screen with better separation between targets that are close to each other. CHIRP sonar is better able to distinguish rocks from vegetation, vegetation from schools of fish, and gravel beds from clay or silt.
Dual Beam Fish Finders
Fish finders that let you choose between transmitting sound pulses in either a wide or narrow beam are called dual beam fish finders. Scanning with the wide beam gives you a broad view of what’s in the water below and around you. Use the wide beam to find an area where the fish are plentiful, and then switch to the narrow beam to see the area in greater detail.
Fish Finders With Side Scan and Down Scan Sonar
More advanced fish finders use both side scan and down scan sonar to scan the water to each side and directly below your location. These fish finders provide you with the most information about the location of the fish.
If you only fish from the shore, you’ll want a fish finder with side-scan sonar.
If you want to see what is directly below where you cast your line, you can get a fish finder with down scan sonar that you can cast out on your line. Some of these create their own Wi-Fi hotspot and transmit their scans to your smartphone.
If you fish from a boat, you’ll want to know about the fish both directly below and all around your position, especially if you fish in salt water from a larger vessel. You’ll want to know if the fish around you start moving off to a new location. In this situation, a fish finder that combines down scan and side scan sonars lets you know if the fish start moving and where they are headed.
I like to fish from the shore, from my canoe, from larger boats that go out in the middle of a lake or out on the ocean. When I buy a fish finder, I look for CHIRP sonar, dual beams, and both down scan and side scan. I want it all, and I use it all.
Some of the navigation features that you’ll find on fish finders include marine radar, compasses, GPS, and the ability to use GPS to set your own waypoints and mark, geotag, landmarks or underwater hazards.
Waypoints are markers that you set to guide you back along a course or a path to an especially successful fishing spot. Geotagging is useful if you fish far offshore or if you go hiking or off-roading in search of remote fishing spots that you hope no one else has found yet. Some fish finders even let you produce maps of your favorite fishing areas. That’s a feature I especially like.
These tools also can help you navigate at night or when fog or a storm reduces visibility as well as helping you to locate fish. I’ve been caught in some pretty thick fogs that rolled in suddenly and unexpectedly. GPS got me back to the marina.
Again, though, you’ll find navigational features most useful if you fish from a kayak or boat or if you go hiking or off-roading to find fishing spots.
If you fish from shore in less remote areas, you won’t need to spend the extra money for the navigational features. You can invest that money in some of your other fishing gear.
Other User-Friendly Fish Finder Features
Some features make a fish finder easier to use regardless of whether you’re using it on shore or on a boat. These include waterproofing, back-lit screens, screens with glare protection, and larger screens.
Check how your fish finder rates for waterproofing, especially if you fish from a kayak. The small size and low profile of your kayak, places your fish finder very close to contact with the water. The higher the rating your fish finder has, the better the waterproofing.
If you fish at night, at dusk, in the early morning, or if the weather reduces visibility, a back-lit screen makes it easier to view the information from your fish finder.
LCD films reduce the glare on your fish finder’s screen from the sun and the water. With these films, you’ll be able to view the screen more easily. You also can turn down the screen’s contrast and brightness, use a shade visor, or move the fish finder into a shaded area.
In general, fish finders with larger screens and displays with a higher number of pixels per inch offer higher quality images. You’ll also be able to see a larger area of the sonar scans that your fish finder produces.
You’ll find screen sizes as small as 3.5 inches and as large as 16 inches. A 9-inch screen is a good mid-range choice for everyone except those who enjoy kayak fishing and for those who go fishing while on hiking and camping trips.
When you’re carrying fishing gear in a kayak, or when you’re carrying camping and fishing gear in a backpack, size and weight become important. For these situations, consider a lighter weight fish finder with a smaller screen. Being able to tuck a smaller fish finder somewhere in the kayak where it is less exposed to the water protects the fish finder and its screen from damage.
What Your Fish Finder’s Screen Is Showing You
The monitor on your fish finder might be in either gray scale or color. It will show you the depth of the lake, river, or stream bed; the depth of the various targets it finds; and the water temperature. If you’re in a boat, it might also show you the speed at which you’re moving. Usually, slower speeds produce the most accurate scans.
Darker colors or shades of gray show harder or more dense targets, like a gravel bed or a rock. Lighter colors show softer, less dense targets, like fish or vegetation.
Basic fish finders display the raw data that they receive back as echoes. These are represented by straight lines and arches. Straight lines show stationary targets. Arches are what you want to see. Those are the fish. The larger the arch, the larger the fish.
More advanced fish finders may give you the option of switching between looking at the display of raw data and Fish ID mode. Fish ID substitutes fish-shaped icons for the fish. Fish finders with Fish ID may also have icons for vegetation, rocks, and other objects. Again, the larger the fish icon, the larger the fish. Fish ID mode sometimes may identify something like a cluster of vegetation as a school of fish.
While my kids loved watching the Fish ID display when they were younger, the raw data mode produces a more accurate display. Now that my sons and daughter are teens, when they go fishing with me, they use raw data mode like their dad.
You can use the information from your fish finder to help identify the types of fish on the display based on several clues:
- By the size of the targets.
- By the speed at which they are swimming.
- By the depth at which they are swimming.
- By the water temperature where they are swimming.
- By whether they are swimming in a school or are more solitary.
- By the type of habitat in which they are located.
This YouTube video entitled How to Read Fish Finder Sonar Technologies from Wired2Fish goes into more detail about what you’ll see on your fish finder display.
The Best Portable Fish Finders
#1 Garmin Striker 4, Striker 4 with Portable Kit, Striker Plus 4, and Striker 4CV
The Garmin Striker 4’s traditional CHIRP down-scan sonar sends pulses sweeping across a range of frequencies. With this sweep, it gathers more information and produces sharper images with distinct target separation and crisper fish arches in both shallow and deep water. The graphics scale smoothly without interrupting the images when you switch between depth ranges.
For vertical jigging or ice fishing, you can switch the display to the classic raw data, flasher format.
Because Garmin’s technology reduces signal noise at even greater depths, you’ll also see clearer bottom contours, even when you’re traveling at higher speeds. The signal reaches a maximum depth of 750 feet in salt water and 1,600 feet in fresh water.
When you’re trolling, you can use the Striker 4’s QuickDraw Contours mapping software to create HD fishing maps of the area with 1-foot contours, and you can save up to 2 million acres of mapped fishing locations. That’s a feature I really like.
If you’re the helpful type, you can share your maps with others who have Striker models or echoMAP chart plotter combos.
With the Strike 4’s GPS, you can mark the locations where the fish have been biting along with boat ramps, docks, underwater hazards like stumps and brush piles, and landmarks along trails to remote fishing streams.
You also can mark waypoints that you can use as navigation guides when returning to the locations where you’ve had fishing success.
With sonar history, you can scroll back through the scans to mark waypoints that you might have missed when creating your routes.
When you’re fishing from a boat, the GPS also lets you track your trolling speed so that you can match your speed to your lure and so that you can stay below the speed required in wake-controlled waters. It’s good to stay legal.
You’ll find the Striker 4’s bright 3.5-, 5-, or 7-inch color display is easy to read in sunlight, and the dedicated buttons create a simple interface that’s easy to understand and use. The Strike 4 has received a water rating of IPX7, which means that it’s rugged enough to stand the test of even challenging fishing environments.
The Garmin Striker 4 with Portable Kit includes a carrying case. When you take your Striker 4 ice fishing or fishing from a kayak or canoe, the case helps to protect it.
The Garmin Striker Plus 4 is the version you want if you fish in deeper waters.
The Garmin Striker 4CV produces a beam with a wider cone than the Striker Dual Beam. This allows you to quickly scan even an even larger area under the boat.
- Crisp, detailed, color display with distinct fish arches and target separation.
- QuickContours lets you map up to 2 million acres of fishing territory.
- GPS allows creation of waypoints for navigating back to your launch point and returning to successful fishing locations.
- GPS also lets you geotag onshore landmarks and underwater obstacles.
- Display lets you track boat speed.
- Dedicated buttons make user interface easy to understand and use.
- Some users complained of poor customer service.
- Some only were able to use their Strike 4 one to two times before it stopped working.
- One user was unable to mount it on a kayak.
- No lake maps are available for the Strike 4.
The Deeper Smart PRO Portable Fish Finder is a great choice when you’re fishing from the shore or trolling from a canoe, kayak, or boat. It’s a dual beam fish finder that creates its own hotspot and connects to your smartphone by Wi-Fi. The display on your phone becomes the display for the scan.
Cast the Deeper Smart PRO out, and it transmits readings on the depth and water temperature. Reel it in slowly, and it maps the contour at the bottom, reads whether the bottom is soft silt or hard gravel, locates underwater obstacles like structures or vegetation, and, most importantly, provides a reading on the location, depth, and size of the fish that are present.
You’ll be able to see how thick the vegetation is and discover the marginal shelves, humps, and depressions that attract carp to an area. If you baited the area, you’ll be able to tell if the fish stayed or moved on.
You can geotag the location of these features using your phone’s GPS.
You also can use the GPS to create bathymetric maps from the shore and save them online for free to Lake Book, Deeper’s bathymetric management platform, using the Fish Deeper app. You can review and analyze your saved maps from your computer, phone, or table from your home or wherever you have a Wi-Fi connection. You can even share your maps if you like.
The wide beam on the Deeper Smart Pro creates a 55° wide scan while the 15° narrow beam reveals the details. The wide scan casts out to 330 feet and reaches down to 260 feet. It produces 15 scans per second with target separations of 0.5 of an inch. You have a choice of three color palettes on the display and a detailed Fish ID-type mode or a basic raw data display.
- Enables the creation of bathymetric maps from the shore as well as while trolling from a kayak, canoe, or boat.
- Transmits its own Wi-Fi signal so that it connects to your smartphone.
- Enables you to upload your maps to Deeper’s Lake Book for later analysis.
- Creates a 55° side scan and a 15° narrow beam that reveals the details.
- Casts out to 330 feet to the side and reaches down to 260 feet.
- A number of users report the Wi-Fi signal is too weak, and the connection is lost.
- Users also report that the depth measurement is inaccurate.
- One user reported not seeing a single fish signal while having a very successful fishing trip.
The Humminbird Helix 5 CHIRP SI GPS G2 offers both side scans and down scans with dual beams and 2D digital CHIRP sonar, but you need to be certain you have selected this specific model.
The side scan and down scan beams capture information in narrow slices, and then add the slices together to build up a richly detailed image.
The side scan reaches out to 1,500 feet, and the down scan reaches down to 2,500 feet.
DualBeam Plus combines the down scan and side scan beams to capture even more detail.
With its CHIRP sonar, dual beams, and side and down scans, the Humminbird Helix 5 creates outstanding, exceptionally accurate, clear images of thermoclines, or temperature changes; fish; the bottom; and underwater structures and obstacles.
With SwitchFire, you have a choice to two display modes on the wide screen, color display – Clear Mode and Max Mode. You can display all the details that the Helix 5 provides, or switch to a less detailed view.
Humminbird Basemap pairs maps of bodies of saltwater from NOAA and maps of bodies of fresh water from LakeMaster with the Helix 5’s GPS so that, even when you’re in unfamiliar waters, you`ll still be able to study the icons on the maps and know the depth and contours of the underwater terrain. This is my favorite feature on this fish finder.
The maps show you depth markings, the water depth at various spot soundings along coastal areas, and the location of marinas, buoys, day markers, hazards, additional navigation aids in the area, and nearby points of interest.
With Autochart Live and built-in Anima cartography, you can create your own maps of the areas you fish in real time and then save them and your waypoints to a micro SD card. Tha’s something else I like about the Helix.
The Helix 5 has a 5-inch, HD, color, WVGA display, and it comes with the transducer, a micro SD port, a gimbal mounting bracket, mounting hardware, a power cable, and a black neoprene cover for when the Helix 5 is mounted with the gimbal mount. One problem, though, is that the cover doesn’t fit properly when the Helix is mounted on the dash of a boat.
- Offers down scans, side scans, and combined down scans and side scans
- CHIRP sonar sends sound pulses over a range of frequencies during scans.
- Has Humminbird BaseMap with clear water maps from LakeMaster and saltwater maps from NOAA built-in
- Humminbird BaseMaps include depth markings in open water, depth soundings near shore, buoys, day markers, hazards, and other navigational aids as well as marinas and nearby points of interest.
- AutoChart Live and Anima Cartography help you create your own maps.
- Use GPS to add your own waypoints.
- Power cable cannot be disconnected from the display so that the display can be connected to a charger, which is a problem for use in kayaks, canoes, and row boats.
- Instruction manual is confusing and unclear.
- Several users said that the depth finder was inaccurate.
- Saves only 500 waypoints without a micro SD card.
- One user complained that the Helix 5 lacked side scan and another that it lacked GPS.
The PIRANHAMAX 4 Fish Finder offers dual beams with a 28° wide beam and a 16° narrow beam scans. Down-scan sonar is included with the PIRANHAMAX 4 DI.
You’ll be able to see the location of fish and the contours of the bottom as well as rocks, timber, vegetation, and other obstacles. You can even zoom in for a closer look.
The Fish Alarm on the PIRANHAMA 4, 4 DI, and 4 PT alerts you when fish are in the area, and Fish ID+ helps you identify the fish. You can also set depth alarms. The user interface has been redesigned to make it simpler to use and easier to understand.
The 4.3 inch color display provides a target separation of 2.5 inches. The wide beam scans a 600 foot area while the narrow beam scans a 320 foot area.
The PIRANHAMAX 4 PT comes with a soft-sided carrying case that protects it from the elements, a transducer that attaches with a suction cup, a 7 AMP HR battery, and a wall charger.
- Offers dual beam scans with down scans included with the PIRANHAMAX 4 DI.
- 28° wide beam for an overall view, and a 16° narrow beam to see more of the details.
- Fish Alarm alerts you when fish are in the area.
- Use the zoom on the display and Fish ID+ to help you identify the fish.
- PIRANHAMAX 4 PT comes with a soft-sided carrying case.
- Users find the PIRANHAMAX 4 a good size for kayaks.
- Lacks GPS for mapping fishing areas and marking waypoints, landmarks, and hazards.
- Some users said the transducer stopped working.
Intended for experienced fisherman, the HawkEye Fishtrax Finder features the Dual-Frequency FishTrax Intelligent Sonar and the Virtuview HD Color Display for a sharper view. With the FishTrax Intelligent Sonar, you can adjust the fish finder to the type of fishing you intend to do, such as shore, kayak, boat, or ice fishing.
Fishtrax Finder locates fish, calculates the depth, provides the temperature of the water, and provides information on the contour and composition of the bottom.
Flasher Mode provides current information, and Fish Finder provides historical information.
In Data Mode, the Hawkeye FishTrax enlarges the readings so that you can read them from a distance.
The Ice-Mode Digital Flasher provides real time sonar information, which is especially good for ice fishing.
To help you better track the fish, the Fishtrax Finder offers 100-level sensitivity adjustment and auto-zoom ground tracking.
The Dual-Frequency (200-kHz and 83-kHz) allows you to select the higher frequency for fishing at a deeper level or the lower frequency for shallower fishing. It provides a 14° to 26° sonar cone and will read to a depth of 240 feet.
The Hawkeye Fish Finder can be mounted on your boat or handheld. The FishTrax includes built in expandability so that you can add accessories.
- The Hawkeye Fishtrax Finder features the Virtuview HD Color Display for a sharper view.
- You can adjust the fish finder to the type of fishing you intend to do.
- It will locate fish, calculate the depth, provide the temperature of the water, and provide information on the contour and composition of the bottom.
- It offers 100-level sensitivity adjustment and auto-zoom ground tracking.
- The Dual-Frequency (200-kHz and 83-kHz) allows you to select the higher frequency for fishing at a deeper level, or the lower frequency for shallower fishing
- It can be mounted on your boat or handheld.
- The FishTrax includes built in expandability so that you can add accessories.
- There are some malfunctioning units that had to be replaced.
- It is splash-resistant, not waterproof.
The LUCKY Portable Fish Finder provides information on the underwater contour, the water depth and temperature, the size of the fish, and the depth of the fish. It offers a 2.4-inch, LCD touch-screen display that provides a clearer image.
With the ability to monitor to a depth of 328 feet and a 26-foot wired operating distance, the Lucky Fish Finder offers a 45° sonar cone and a high-frequency of 200-kilohertz (kHz). This high frequency is for depths of more than 200 feet (60 meters) and for receiving more accurate and detailed readings at faster speeds.
High-frequency transducers, however, do have a more limited coverage area.
With sensitivity settings ranging from one to ten, you can choose three underwater contour displays, screen brightness, light sensitivity, zoom, fish alarm, fish icon, depth alert, language, and measurement units such as foot, meter, Centigrade, and Fahrenheit.
With a level-four spray water-proof rating, you can use the Lucky fish finder whether you are at the shore, on the river, sailing the sea, or going ice fishing.
Using the bracket, you can attach it to the hull of your boat, cast it into the water with a float, or clear off snow, lay it flat on smooth ice, and drill a hole for ice fishing.
If you’ve never used a fish finder before, the LUCKY Fish Finder includes a simulator mode so that you can try out its features and learn how o use them.
The LUCKY Fish Finder can be used in temperatures ranging from 14° to 122° Fahrenheit (-10° to 50° Centigrade). This uses 3.7-volt rechargeable lithium batteries. It comes with a USB cable for charging and a lighted cap for night fishing. A charge lasts around five hours.
- The Lucky Fish Finder can be used for shore, river, sea, or ice fishing.
- Along with the transducer, it offers a simulator to help you learn how to use it.
- It provides information on underwater contour, water depth and temperature, the size of the fish, and the depth of the fish.
- The high-frequency transducer is best for depths of more than 200 feet (60 meters) and for receiving more accurate and detailed readings at faster speeds.
- It is portable, rechargeable using 3.7-volt rechargeable lithium batteries, provides a USB cable for charging, and includes a lighted cap for night fishing.
- The Lucky Fish Finder can be used in temperatures ranging from 14° to 122° Fahrenheit (-10° to 50° Centigrade).
- Although the instructions tell users to place the fish finder on the hull of a boat below the water line, the fish finder is not waterproof.
- The screen is hard to read in the sunlight.
With familiar smartphone-like menus that provide one-touch access to key features, the Lowrance HOOK2 5 Fish Finder is easy to learn to use. You can spend your time fishing instead of setting your fish finder.
The HOOK2 5 features an auto-tuning, wide-angle, CHIRP sonar cone that provides twice the coverage of standard fish finders. This is especially useful for kayaks and smaller boats since you’ll only need one fish finder.
The TripleShot transducer provides a DownScan sonar, a SideScan sonar with a maximum 300-foot view on each side, and the CHIRP sonar with the fish arch view.
The pre-loaded, high-detail US inland lake mapping includes 4,000 lakes with 1-foot contours to help you locate drop offs, ledges, and cover where fish might be hiding.
The GPS plotter helps you navigate and follow and mark trails.
An SD card slot lets you add software and mapping upgrades, third-party maps, and future features.
The high-resolution Solarmax Display gives you clear views and daylight visibility. You can choose a 5-, 7-, 9- or 12-inch screen.
- Smartphone-style menus create one-touch access to key features, making the HOOK2 5 easy to set.
- The wide-angle sonar cone searches twice the area of standard fish finders.
- The transducer provides a down scan, a side scan, and a fish arch view.
- A pre-loaded mapping feature includes 4,000 US inland lakes, allowing you to locate drop offs, ledges, and cover where fish might hide, even in lakes you don’t know.
- The GPS helps you navigate, follow, and mark trails.
- The high-resolution Solarmax Display is easy to view in sunlight and on the water.
- The Lowrance HOOK2 5 Fish Finder is available with a 5-, 7-, 9- or 12-inch screen.
- The plastic transducer bracket is molded to the transducer. If it breaks, you’ll need to buy a new transducer and not just the bracket.
- A design issue can cause air pressure to build causing a lack of power supply to the transducer.
The Best Portable Fish Finder
Choosing the best portable fish finder from my recommendations was pretty difficult. I finally based my choice on how each of the fish finders could be used and came up with two winners.
First, for those who fish in familiar, easily accessible areas who don’t need GPS, I chose Humminbird’s PIRANHAMAX 4 series. It offers you a dual scan sonar, and if you fish from a boat, you can purchase the PIRANHAMAX 4 DI and have a down scan sonar. The PIRANHAMAX 4 PT comes with a suction mounted transducer, a protective carrying case, and a battery for those who fish from kayaks, canoes, and rowboats.
For those who want a fish finder that does it all, I chose the Humminbird Helix 5 CHIRP SI GPS G2 as my winner, but as I said, you have to be certain that you select the right model. With this model, you get both down scan and side scans from a dual-beam and 2D CHIRP sonar. You have built-in access to Humminbird’s Basemap, which provides you with detailed maps of bodies of saltwater from NOAA and bodies of freshwater from Lake Master. In addition to the navigational aids and points of interest that come with these maps, you can use GPS to add your own waypoints. You also can use the GPS with AutoChart Live and Anima Cartography to create your own maps.
Even if you choose one of my other picks from this list, though, you’ll still have a winner.