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When you’re out looking for fish finder reviews, you’re probably overwhelmed by the amount of fishing writers reviewing $2,000 fish finders (myself included).
I want you to know that you don’t need a pricey fish finder to catch fish. If you’re looking for the best fish finder under 100, just know that you can find it, and it will work.
The main thing to understand is that these fish finders won’t have fancy live features, GPS, or 12-inch screens. You’ll need to make some sacrifices.
But the truth is, they’ll find fish just as good as any other unit. Take our top pick, the Humminbird PiranhaMAX 4 for example. This model came out almost 10 years ago and it’s still being sold.
They’re not selling it 10 years later because it doesn’t work!
Let’s take a look at some affordable units you can get your hands on today.
Table of Contents
Best Overall Fish Finder Under $100
Humminbird PiranhaMAX 4
Specs
- Screen: 4.3-inch
- Sonar: 200/455 kHz
- Max Depth: 600-feet
- Warranty: One year
Pros
- Dual beam sonar
- Color display for differentiating structure
- 600-foot depth
Cons
- Lacks GPS or charting
Why We Chose It
This unit comes in right around $100 (it might be a tad over) but I think it’s well worth the extra few bucks!
The Humminbird PiranhaMAX 4 is a feature-rich fish finder at an affordable price. It comes with a 4.3-inch color screen offering accurate readings of structure and fish underwater.
This is 8-inches larger than the previous PiranhaMAX which I fished for years.
The device uses DualBeam PLUS sonar technology which can cover a wide area, making it easier to differentiate schools of fish from structure. It offers a 200 and 455 kHz frequency.
One of the standout features of the Humminbird PiranhaMAX 4 is its depth capability. It can reach depths of up to 600 feet, which makes it a great choice for bass anglers with a boat.
In my experience, if you’re shopping for the best fish finder under 100, the most important thing you’re looking for is reliability and consistent performance. You’ll be certain to get that in the PiranhaMAX 4.
Click here to read my full review of the Humminbird PiranhaMAX 4!
Best Fish Finder for Kayak Under $100
LUCKY Portable Fish Finder
Specs
- Screen: 2.8-inch
- Sonar: Single beam fish alarm
- Max Depth: 328-feet
- Warranty: One year
Pros
- Super simple to install and use
- Portable for kayak use
- Super cheap at less than $50
Cons
- Really simple technology, a bit lacking
Why We Chose It
If you’re in the market for the best kayak fish finder under $100, this is the one for a couple of different reasons.
Despite its affordable price, it packs a lot of features into its compact design. With a 2.8-inch color TFT LCD display, the device provides clear and accurate readings of fish under the water using basic Fish ID images.
The LUCKY Fish Finder uses sonar technology to reach depths of up to 328 feet and has a 90-degree beam angle so it’s a great choice for both kayak and shore fishing.
One of the standout features of the LUCKY Portable Fish Finder is its portability. It can be mounted on a fishing rod, transom, or float, making it a great choice for anglers who like to fish from a variety of locations.
It’s also not designed to be permanently mounted to a boat which makes it the best kayak fish finder. You can install it prior to getting in the water and then take the transducer off when you’re done for the day.
The device is also easy to use, with a user-friendly interface and simple menu navigation. It’s powered with 4-AAA batteries and lasts up to five hours.
All in all, the LUCKY Portable Fish Finder is a great choice for anglers looking for an affordable, yet feature-rich fish finder.
Easiest Fish Finder to Use Under $100
ReelSonar iBobber
Specs
- Screen: n/a
- Sonar: Single 90-degree scan
- Max Depth: 135-feet
- Warranty: One year
Pros
- Connects directly to your Android or iPhone
- Castable unit is great for shore fishing
- Lightweight and easy to transport
Cons
- Requires a means of actually casting it into the water
Why We Chose It
If you know me, you know I’m a fan of my castable fish finders. That said, this is the cheapest one on the market so as you can imagine, you’re going to have to make some sacrifices.
The ReelSonar iBobber is great if you’re looking for something that is easy to use and convenient for fishing anywhere.
This device connects to a smartphone or tablet via Bluetooth, allowing anglers to use their mobile device as a display screen.
The ReelSonar uses sonar technology to reach depths of up to 135 feet and provides clear and accurate readings of everything right on your smartphone.
The thing I enjoy most about this fish finder is how easy it is to use and how simple it is to connect to your phone. It’s compact and lightweight, making it easy to transport and use in a variety of fishing conditions.
The ReelSonar also comes with a built-in rechargeable battery (10+ hours), so anglers don’t have to worry about constantly buying and replacing batteries.
If you’re the kind of angler who fishes most often from the shore and is looking for a budget unit that’s easy to set up, this is definitely a great option.
Best Castable Fish Finder Under $100
Deeper START Smart Fish Finder
Specs
- Screen: n/a
- Sonar: Single 40-degree beam
- Max Depth: 165-feet
- Warranty: Two years
Pros
- 165-foot range
- Two-inch target separation
- Lightweight and super portable
Cons
- Only one single 40-degree sonar beam means a lot of dead space on your readings
Why We Chose It
Let’s take another look at a castable unit, this time from Deeper. The Deeper START Smart Fish Finder is a castable fish finder that provides anglers with an efficient way to locate fish.
With its compact design, the device can be easily cast from the shore or from a boat, providing a comprehensive view of everything happening around you and beneath you.
The Deeper START uses dual-frequency sonar technology to reach depths of up to 165 feet and you’ll connect the sonar device to your mobile phone and use it as your display.
There’s no need for a wifi connection with this wireless fish finder.
The down imaging unit has a built-in rechargeable battery with a battery life of around six hours.
An immediate drawback I see which is kind of surprising is the fact that this unit only has a single 40-degree beam which is unusual when the iBobber offers a 90-degree scan.
To explain this in simpler terms, you’re not going to get as wide of a scanning beam from the Deeper START so you’ll need to be really precise on your cast to ensure you’re scanning the water you actually intend to fish.
Either way, I think this is one of the better options for fish finders under 100. You really can’t go wrong.
Resources
I’d like to point out that there’s nothing wrong with shopping on a budget and if you don’t fish a ton, you don’t need to spend a lot of money on a fish finder anyway.
These will provide you with a better idea of where the fish are and that’s what fish finders were designed to do anyway.
The best fish finder under 100 is usually the fish finder many beginners should use to get their feet wet.
In today’s world, we’re always looking for ways to enhance the experience with larger screens, live readings, and other various functions; but in reality, you don’t need those things.
All you need a basic fish finder to do is:
- Provide fish depth
- Provide fish location
- Differentiate types of fish and size
- Include water depth and water temperature
These four features will help you identify the best fishing spots.
That said, here’s a few resources to help you learn more about the different types of features you can get in more advanced fish finders.
For an overview of the best fish finders overall: Check out our best fish finder review
If you’d like to learn more about fish finders that offer GPS and mapping: Check out our best GPS and mapping fish finders
Planning on fishing the hard water this year? Check out our best ice fishing fish finders
If you can afford CHIRP sonar in the $125-150 range: Check out the Garmin Striker 4
Frequently Asked Questions
What are the best cheap fish finders?
The best cheap fish finders are outlined in this guide with the Humminbird PiranhaMAX 4 being the best one of all.
Do cheap fish finders work?
Cheap fish finders absolutely work and sometimes better than their expensive counterparts. They just lack the fancy features and bells and whistles of premium units.
Final Thoughts
If you’re in the market for the best fish finder under 100, don’t think you need to settle for some silly kids toy; you can get yourself a great fish finder that does exactly what you’re looking for.
I recommend going with the PiranhaMAX 4 because it’s the closest thing to a premium fish finder on this list. If you prefer something that is more portable and castable, I’d choose the iBobber in this case.
Let me know if you put any of these to good use this season. Leave me a comment and tell the readers how the fish finder impacted your ability to pull in some bass!
