Garmin Edge 850 vs. Hammerhead Karoo 3: Which One to Buy?

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I bought Edge 850 and Karoo 3, so you don’t have to. Then I tested them and compared them thoroughly to help you decide whether they are worth it or if you should consider alternatives.

Edge 850 vs. Karoo 3: The Basics

The table below compares the technical specifications of the Garmin Edge 850 and Hammerhead Karoo 3.

Edge 850 vs. Karoo 3: Features Comparison and Differences

Physical Dimensions & Weight

Edge 850 and Karoo 3 have similar dimensions, but the Karoo 3 is taller. They are mid-sized head units, ideal for most scenarios, and my preferred size. I find the Edge 1050, ELEMNT ACE, and similar bike computers too big for casual riding. On the other hand, if you have poor eyesight, you might benefit from them. Despite their different form factor, the E850 and Karoo 3 weigh almost the same (±6 grams).

Ease of Setup

To set up both bike computers, all you have to do is scan a QR code. If you have already been using a Garmin Edge bike computer, its settings, such as the data pages, data fields, and sensors, will be downloaded from the cloud. This leaves you with a ready-to-use unit. You can also adjust most settings directly on the Edge 850, or alternatively, via the Garmin Connect smartphone app.

Karoo 3 also synchronizes data fields and sensors (if you have used a Karoo device before). However, it cannot be customized using a smartphone app; all settings can be configured directly on the head unit.

I declare Edge 850 the winner because it also allows customization through the Garmin Connect app. Aside from that, it is pretty close.

Winner: Edge 850

Display

The 3.2″ display size of the Karoo 3 is 0.5″ larger than that of the Edge 850 (2.7″). Since both head units are limited to 10 data fields, the screen size matters because the fonts are larger and easier to read on the Karoo 3. The larger screen real estate simply has some benefits.

Both these head units are also brighter than average. They almost reach smartphone levels, making them easy to read in most scenarios. See the following gallery for illustration. In reality, the Karoo 3 is slightly brighter than the Edge (though some photos make it look the opposite).

The resolution is similar, and both displays look sharp, as shown in the following close-ups.

Winner: It’s a draw

Control & User Friendliness

The user-friendliness is similar, but the Karoo 3 feels simpler to use. This might be because its system is closer to Android, which is familiar to many of us, and has fewer features. One of Edge’s advantages (its huge feature set) is also one of its downsides, as it makes the entire system clunkier.

Surprisingly, Karoo 3 won’t let you adjust many settings in the smartphone app. The app is primarily used to sync routes, activities, and notifications from your smartphone. Everything else has to be set up directly on the head unit. I like the vast customization options for the appearance of the data fields. Garmin offers far fewer customization options. It almost feels like comparing Android vs. iOS.

I also find it fascinating to see how Hammerhead continuously improves its software. I turned the Karoo on after a few months, and after updating it, it featured several new features. Hammerhead also does a good job explaining what’s new (unlike Garmin), immediately “directing” you into the menu settings for a given feature if you want to. I’m not saying Garmin doesn’t push firmware updates; it does. But Garmin does a much worse job of presenting the improvements.

In terms of control, both bike computers have touchscreens and control buttons, making them highly flexible and suitable for all conditions. I slightly prefer Garmin’s button placement because the Karoo lacks the “main” buttons at the bottom. But I can live without them. The buttons on both devices feel tactile and easy to press, but the Karoo’s buttons feel cheaper.

So, what about the performance in wet conditions or with gloves? Watch the following videos. Both displays perform pretty well.

Garmin Edge bike computers might feel a bit overwhelming, especially the first time you use them. They have a steeper learning curve because there are so many features and options. On the other hand, their performance is smoother. The Karoo system sometimes stutters, especially when pulling the top widget. This is the only flaw. Otherwise, I am satisfied with the system.

Considering the cleaner UI, more modern approach, and better presentation of new features, I call Karoo 3 the winner here.

Winner: Karoo 3

Battery Life

The Edge 850 has a claimed battery life of 12 hours. My E850 lasted 10.3 hours in real-world testing. The Karoo 3 lasted about 2 hours longer (~12.3 hours); however, its claimed battery life is 15 hours. That said, the battery life of both units is underwhelming. They simply traded a brighter display for shorter battery life than some of the best bike computers, as shown in the chart below.

I used both bike computers with auto-brightness settings enabled (both have ambient sensors to adjust brightness) and kept the same set of sensors connected to both.

Winner: Karoo 3

Maps & Navigation

This is an area where the Edge 850 has an advantage. Its navigation is simply more detailed and provides more granular instructions than Karoo 3. Both units are great for navigation: they let you browse maps by touch and are reliable, but Garmin is simply in a league of its own. The only thing that bothers me is the size of the map regions. It’s unfortunate to have to download gigabytes of data just to update maps for a specific country.

Winner: It’s a draw

Accuracy

Thanks to the Multi-Band GNSS system, which enables simultaneous reception of satellite signals across multiple frequency bands and global systems, both units should be quite accurate. However, this technology alone can’t guarantee the same level of accuracy between two competing devices. So, what was the reality?

I usually test bike computers on my favorite forest segment, but this time, I used Karoo 3 near Lake Como in Italy. It was not as accurate as I expected, especially in densely forested areas. Unfortunately, I haven’t tested them side by side. Such testing could reveal that Edge 850 would also struggle in that area. In any case, the accuracy is generally good enough. Based on my testing, the Edge 850 appears more accurate.

Winner: Edge 850

Extras

Both units can display information about upcoming climbs. These features are called ClimbPro (Garmin) and Climber (Hammerhead) and are some of my favorites. They don’t require a planned route, so I can pace myself more effectively on climbs that I’m not familiar with. I’ve done a comprehensive comparison of these two and Wahoo’s Free Summit. In summary, the ClimbPro data page is less customizable than the Climber data page. Climber is better integrated because it can be displayed on your main data page as a hidden tab instead of on two separate data pages.

Winner: Edge 850

Total score: Garmin Edge 850 (3) | Hammerhead Karoo 3 (2) | It’s a draw (2)

Garmin Edge 850 and Karoo 3 Alternatives

If you don’t want a Garmin Edge 850 or Karoo 3, consider these alternatives:

• The Garmin Edge 840 and Garmin Edge 1040s are previous-generation Edge bike computers with much longer battery life, but a somewhat reduced feature set.
• Wahoo ELEMNT ROAM 3 is simpler and easier to use, and offers a longer battery life. On the other hand, it doesn’t have as many features.

Summary

After comparing several categories, Edge 850 beats Karoo 3, but it’s as close as it gets. I slightly prefer the Karoo 3 because of its more modern approach. However, I would likely miss the Garmin ecosystem, especially having my data in Garmin Connect. I sometimes use a Garmin smartwatch for swimming and running, so having my data in one place (not just on Strava) that also evaluates my training load and fatigue is beneficial.

Also, the price difference between these two units is significant. The Edge 850 costs $599 while the Karoo 3 costs “only” $475. For some, this price difference can be significant enough to choose the Karoo.

Before pulling the trigger, consider whether you can leverage the fancy Garmin features, and if you don’t mind the short battery life. Personally, I would rather buy the Edge 840 over these two, even though it has a dimmer display.

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