Ice Fishing Fish Finder Vs Flasher (Detailed Comparison)


by Robert Ceran

Ice fishing electronics have come a long way over the past decades, and they are now so good that they dramatically improve the ability of anglers to catch fish under the ice.

So if you want to catch more fish with ice fishing, getting a good sonar device to help you find and catch fish more effectively is definitely worth it.

The only challenge with this is that you need to choose between two different types of sonar: either a flasher or an ice fishing fish finder. 

So what are the differences between a fish finder and a flasher, and which one is better for ice fishing?

In this article we’ll go over the key differences between them, as well as their pros and cons, to help you decide which one is right for you.

What is the difference between a fish finder and a flasher?

The main difference between a fish finder and a flasher is the way that sonar signals are displayed.

A flasher shows real-time sonar data from the water column right underneath the ice hole, while a fish finder shows historical sonar data of the last few minutes.

Because of this difference, a flasher is sometimes referred to as a one dimensional sonar, and a fish finder as a two dimensional sonar.

Flashers were developed to show what’s going underneath your ice hole in the present moment, while ignoring everything else.

Since ice fishing is a vertical fishing tactic, it’s usually not important to see historical data of what happened underneath your ice hole a few minutes ago, while it’s extremely helpful to get a real-time read out of what is happening there right now.

Flashers were specifically developed for ice fishing, and are rarely used for any other type of fishing.

Fish finders, on the other hand, were originally developed for use on a boat moving in open water, where it can be very useful to see the structures and fish that passed through your sonar cone a few minutes ago, as you can circle back to them.

Having said that, however, you can definitely use a fish finder for ice fishing, by simply focusing on the most recent sonar signals, which will tell you what’s going on underneath your ice hole right now.

In fact, many modern fish finders have a real time sonar (RTS) function on the right side of their display, which is ideal for this purpose.

Let’s look at some additional differences between flashers and fish finders:

  • Display: Fish finders come with an LCD display, while flashers have a fiber optic display lit by LED lights. A fiber optic display is much less sophisticated than an LCD, but many flasher fans see this as an advantage. A flasher display focuses on a few key objects (the bottom, your lure, and any fish swimming in the water column under your ice hole) and displays these objects in crisp resolution as brightly colored lines on a 1-D display. A key advantage of the fiber optic display is that it uses much less power than an LCD display, and it’s also easier to see in bright light conditions.
  • GPS: Most fish finder units come with built-in GPS and mapping capabilities, while flashers don’t have these functionalities. Needless to say, these features can be very useful to find promising ice fishing spots.
  • Battery life: Flashers tend to have longer battery life compared to fish finders, due their fiber optic display requiring much less power compared to the LCD display of a fish finder. As a result, you can expect a flasher battery charge to last 2-4 times longer than that of a fish finder.
  • Portability: Flashers come with portable packs that contain all necessary components, including battery and transducer, while most fish finders don’t come with this, and you’ll have to purchase it separately.
  • All-season usability: While fish finders can be used both during ice fishing and open water season, flashers are only really suitable for ice fishing. 

Are fish finders different for ice fishing?

Ice fishing fish finders are different from open water fish finders in 4 key ways:

  1. They come with an ice transducer built to withstand colder temperatures compared to open water transducers. Ice transducers are also fitted with a floating device to position them pointing downwards vertically in an ice hole.
  1. The top models have been designed to eliminate lag time in their sonar display. This results in close to real-time sonar signal display, and puts them on a par with flasher units. In contrast, open water fish finders tend to have a slight lag time when reporting the most recent sonar returns.
  1. Their LCD display is designed to function reliably in subzero temperatures.
  1. They have a flasher functionality on their display, which allows you to view sonar signals in the same configuration as on a flasher screen. Combined with the reduced lag time, this allows you to see what’s going on in the water column in a highly dynamic, real-time fashion, and with a similar high resolution as on a flasher display.

In addition to these features, ice fishing fish finders also come with most of the features of regular open water fish finders, including split screen functionality, GPS, mapping capabilities, and so on.

So overall, ice fishing fish finders are designed to combine the main functionalities of flashers with those of regular sonar units.

Can you use a regular fish finder for ice fishing?

Yes, you can use a regular fish finder for ice fishing, but it’s best to replace the open water transducer with an ice transducer.

Also keep in mind that you’ll need a bigger battery, a back up battery, or lithium batteries (which last longer), since the battery charge runs out faster in cold temperatures.

You’ll also need to get a carrying pack to transport all of the components out on the ice.

What is flasher mode on a fish finder?

Flasher mode on a fish finder is a functionality that displays sonar data in the form of a circle, similar to the fiber optic display of a flasher.

So if you’re used to reading the display of a flasher for ice fishing, you can get the same results with a fish finder that has flasher mode. 

Are ice fishing flashers worth it?

Ice fishing flashers are absolutely worth buying if you’re a highly committed ice angler, since they are ideally suited for this type of fishing.

Flashers have the edge over fish finders in terms of being able to display real-time information of what’s going on underneath your ice hole, and at an extremely high resolution.

The two most important brands of flashers are Marcum and Vexilar.

What type of sonar is best for ice fishing?

Now let’s summarise the most important facts you need to know in order to decide what option is best for you:

  • The main advantages of flashers is that they provide an accurate real-time view of the water column at a very high resolution, and they also come with a high battery life, are easy to use, and are highly portable. 
  • The main advantages of ice fishing fish finders is that they come with GPS and mapping capabilities, have split screen functionality, and can be used both on ice and during open water season. 


In terms of pricing, there is no real difference between these two types of ice fishing sonar, which both have a price range between 300 and 750 dollars.

Ice fishing fish finder vs flasher – which one should you get?

Recent advances in the display technology of ice fishing fish finders has improved their lag time, and as a result they can display sonar signals almost as close to real time as flashers.

So, since they come with all other advantages of fish finders, including GPS, mapping, and all-season usability, in our opinion ice fishing fish finders provide considerably more value than flashers, while retailing at the same price.

So, especially if you’re relatively new to ice fishing, I recommend you get a good ice fishing fish finder that you can use all year round.

On the other hand, if you’re a highly dedicated ice angler who doesn’t mind the extra cost of getting a sonar you can only use during winter season, you may prefer getting a flasher.