Ninja DualBrew vs Keurig K-Duo

This is our Ninja DualBrew vs Keurig K-Duo coffee maker comparison guide.

The Ninja DualBrew and the K-Duo are very flexible and practical brewers that are in high demand and for many good reasons, especially because they are capable of brewing both single cups and full carafes.

After our in-depth analysis, we consider the Ninja DualBrew to be the best model, but why?

Let’s find out.


Ninja DualBrew

Ninja DualBrew

Keurig K-Duo

Keurig K-Duo

This comparative guide is quite long, so for that reason, we will give those quick readers a summary of which machine is better.

Overall, the Ninja DualBrew is better than the Keurig K-Duo because of these reasons:

  • Produces hotter coffee
  • Comes with a wider variety of brew sizes to choose from
  • Comes with an independent water dispenser
  • It is more compact and the position of its water tank allows you to be more flexible as to where you can place it in your kitchen

The Keurig K-Duo, although a reliable option, has fewer features, and since they are about the same price, it is more reasonable to buy the Ninja DualBrew.

Note that you can also buy the Ninja DualBrew Pro which comes with even more features than the standard model. We recommend this model if you find a good price.

Here is an introductory video of the Ninja DualBrew:

And, here is an introductory video of the Keurig K-Duo:

Comparison Table

SpecificationsNinja DualBrewNinja DualBrew ProKeurig K-Duo
Brew Sizes8, 10, 12, 15, 18, 28, 37, 46, 55 cups (carafe), and 6oz, 8oz, 10oz, 12oz (single serve)8, 10, 12, 15, 18, 28, 37, 46, 55 cups (carafe), and 6oz, 8oz, 10oz, 12oz (single serve)6, 8, 10, 12 cups (carafe) and a 6oz, 8oz, 10oz, or 12oz (single serve)
Water Tank Capacity60oz60oz60oz
Adjustable Water Tank✔️
Removable Water Reservoir✔️✔️✔️
Charcoal Filter Compatibility✔️
Product Dimensions15.4″H x  11.18″W x  9.08″D (Overall)15.54″H x 11.39″W x 9.13″D (Overall)12.9″ H x 10.9″ W x 12.7″ D (Overall)
ColorsBlackBlackBlack, Silver
Strength Controls✔️✔️✔️
Travel Mug Friendly✔️✔️✔️
Hot Water On Demand✔️✔️✔️
Independent Hot Water Dispenser✔️✔️
Integrated Milk Frother✔️
Auto Brew (Scheduled Brew)✔️✔️✔️
Auto Pause and PourCarafe and Single ServeCarafe and Single ServeCarafe Only
Heating Plate✔️✔️✔️
Power Cord Lenght29″29″30”

Key Features: Keurig K-Duo vs Ninja DualBrew

There are a lot of differences between the Ninja DualBrew and the Keurig K-Duo, so, to make things simple, we are going to divide them into several categories like water reservoir, performance, capsule compatibility, and more.

We are also going to include some information about the Ninja DualBrew Pro since it is highly requested by users due to its features.

Brew Sizes

One of the things that makes these machines so versatile is that they can brew single cups or a full carafe.

These are the brew sizes of the DualBrew and DualBrew Pro:

  • 4 pod brew sizes
    • 6oz
    • 8oz
    • 10oz
    • 12oz
  • 9 grounds brew sizes
    • 8oz (Small Cup)
    • 10oz (Cup)
    • 12oz (XL Cup)
    • 15oz (Travel Mug)
    • 18oz (XL Travel Mug)
    • 28oz (¼ Carafe)
    • 37oz (½ Carafe)
    • 46oz (¾ Carafe)
    • 55oz (Full Carafe)

These are the brew sizes of the Keurig K-Duo:

  • 4 pod brew sizes
    • 6oz
    • 8oz
    • 10oz
    • 12oz
  • 4 grounds brew sizes
    • 30oz
    • 40oz
    • 50oz
    • 60oz

As you can see, the Ninja DualBrew models offer a wider variety of brew sizes.

Winner: Ninja DualBrew & DualBrew Pro

Water Reservoir

The Keurig K-Duo has a large 60oz removable water reservoir, note that both the pod and carafe brewing options draw water from this single reservoir, which is very convenient.

This water reservoir is very wide and has a couple of slots on the back that can be used to pull it out with your hands.

In addition, the tank has markings that allow you to see the exact amount of water it contains.

This water tank has one major drawback, placing the machine with the tank close to the wall or in a narrow space can make removing it quite uncomfortable. This is due to its design.

The Ninja DualBrew has a large 60oz removable water tank that is placed on the right side of the machine.

It is quite different from the one on the K-Duo as this one is a bit taller, and not as wide, however, it does have a rather nice carrying handle and some markings to know how much water is in the tank.

The tank on the Ninja DualBrew Pro is adjustable, so you can change its position from the right side to the back of the machine if you wish. This is one of its biggest advantages over the other models.

The winners in this aspect are the Ninja DualBrew and DualBrew Pro due to the position of their tanks. Additionally, the tank of the Ninja DualBrew Pro is adjustable, which is extremely useful.

Winner: Ninja DualBrew Pro

Ease of Use

We can talk all day about how easy or difficult it is to use these machines, however, we are going to keep it short so we can save you some valuable time.

The Keurig K-Duo’s display is very easy to understand, only showing a little information such as the current time.

Its controls are also very simple, it has just 12 buttons.

  • 4 buttons to choose the brew size
  • 2 buttons to select between pod and carafe
  • Button for setting up auto brew
  • 2 buttons to change the time
  • Power button
  • Strong button
  • Start brew button

To brew a cup of coffee you just have to turn on the machine, select your brewing mode and choose brew size, insert a coffee pod or grounds and press the BREW button.

Now, let’s talk about the Ninja DualBrew.

The interface on the Ninja DualBrew is simple, it has a lot of indicator lights that tell you when to descale the machine, and the brewing mode you have selected.

Contrary to the K-Duo, this one doesn’t have a lot of buttons, instead, it has a control knob that you can use to select between the brew sizes available.

These are the buttons this machine has:

  • Power button
  • Brew style button
  • Start brew button
  • Keep warm button
  • Delay button (auto brew)
  • Hr/Min button (to adjust time)
  • Clean button (to activate cleaning mode)

Now, brewing a cup of coffee can take a couple of extra steps than the K-Duo, the process is almost the same, however, when selecting the brewing mode (carafe or pod), instead of just pressing a button, you have to insert or remove the Ninja pod adapter.

Note that this only applies depending on the brewing mode you want to use. If you had the pod adapted inserted, there’s no need to do this.

In summary, brewing coffee in both machines is fairly straightforward, but because of the extra step needed to brew with the Ninja DualBrew, we’re going to say that the Keurig K-Duo is easier to use.

Check the manuals of the Ninja DualBrew and K-Duo here.

Winner: Keurig K-Duo

Brew Quality and Performance

Let’s talk about the differences between the Ninja DualBrew vs Keurig K-Duo in terms of brew quality and performance.

Speed, Temperature, and Flavor

We tried to brew an 8oz cup of coffee with both machines and they took about 1 minute.

When brewing in a carafe, it is about 1 minute per cup, so the time will change depending on how many cups you want to brew.

One advantage of these machines is that they don’t need a lot of time to preheat before brewing a cup of coffee, the warm-up time is almost instant on both of them.

In terms of temperature, the coffee made with the Ninja DualBrew was about 170F while the one made with the K-Duo was about 165F.

Regarding flavor, they both produce “standard” coffee, a nice feature of these machines is that you can use the strong brew mode to increase the boldness of your coffee.

Extra Brewing Modes

The Ninja DualBrew comes with an extra brewing mode called “Over Ice”. This mode is especially useful for making (as the name suggests) over ice coffee.

It works a little differently than the other modes because the brewing process automatically starts and stops several times to make sure the hot coffee doesn’t melt the ice too quickly.

Keep in mind that for this mode to work properly you must have the mug or carafe full of ice.

The Ninja DualBrew Pro comes with another extra mode called “Specialty” that allows you to brew specialty drinks like macchiatos, cappuccinos, and more.

To summarize, we can say that they both are pretty equal when it comes to brewing quality and performance, however, the Ninja DualBrew and DualBrew Pro are superior because they produce hotter coffee, and come with more brewing modes.

Winner: Ninja DualBrew & DualBrew Pro

Capsule and Filter Compatibility

Both machines are fully compatible with any K-cup.

When brewing coffee in a carafe, keep in mind that both machines require you to use a paper filter.

A good thing about these machines is that they are compatible with reusable coffee filters for pod and carafe brewing.

Actually, according to some reviews, some users have bought reusable coffee filters for this coffee maker that were supposed to be compatible, but in the end, they turned out not to be.

Anyways, here you have some options.

Reusable coffee filters for the Keurig K-Duo:

Reusable coffee filters for the Ninja DualBrew:

Winner: Tie

Cleaning and Maintenance

When comparing the Keurig K-Duo vs Ninja DualBrew, there’s one thing that they share (and every single coffee maker to be honest) and it is that they require constant cleaning and maintenance to work properly.

Let’s quickly summarize in a few points what you should do to clean these coffee makers from time to time.

  • Both machines require you to do a cleansing brew before brewing your first cup of coffee. This applies to carafe and single-serve.
  • After brewing hot cocoa or strong flavors, it is recommended to run a cleansing brew.
  • It is recommended to clean the exterior, drip tray, and water tank of your machine with a damp, soapy, lint-free, non-abrasive cloth. Remember to not dry the inside of the reservoir with a cloth as lint may remain. Make sure to clean slightly the parts of the machine after each use and perform an in-depth cleaning at least once per week.
  • You should perform a descaling cycle when the descaling light on your machine is on.

If you need more information on how to clean your particular machine, you can consult their manuals.

Here’s an example.

Keurig K-Duo User Manual: Caring for your Coffee Maker

Here’s a detailed video on how to clean the K-Duo.

Here’s a detailed video on how to clean the Ninja DualBrew and DualBrew Pro.

As we said before, both machines require constant cleaning and maintenance, so none is better in this aspect.

Winner: Tie

Additional Features

In this section of our Ninja DualBrew vs Keurig K-Duo comparison guide you will learn more about how they compare to each other in terms of additional features.

Auto Brew

All of these machines include an Auto Brew function (Ninja calls this function “delayed brew”).

This means that you can program your machine to start brewing coffee automatically at the time you program it. Pretty convenient right?

Check this video to learn how to configure this feature on the Ninja DualBrew:

Or, you can check this video to learn how to configure this feature on the Keurig K-Duo:

Pause and Pour

The Ninja DualBrew and DualBrew Pro have a lever called “the drip stop”, which is used to pause the brewing process manually. This only works for 30 seconds. 

If you forget to resume the brewing process using the drip stop, the machine will cancel the process automatically after 5 minutes.

This feature works for both pod brewing and carafe brewing.

On the other hand, the K-Duo has an automatic Pause and Pour system that allows you to pause the process while brewing a carafe for 20 seconds. Keep in mind that this feature only works for carafe brewing.

Auto Off

The Ninja DualBrew and the Keurig K-Duo have an auto-off feature, which, as the name suggests, turns off the machine automatically after the last brew after a few minutes.

This is useful for saving energy.

To learn more about how this feature works, make sure to consult their manuals.

Other Features

To not keep this comparison too long, here we are going to list other features that these machines have.

  • Hot water on-demand (Keurig K-Duo, Ninja DualBrew and DualBrew Pro)
  • Independent hot water dispenser (Ninja DualBrew and DualBrew Pro)
  • Integrated milk frother (Ninja DualBrew Pro)
  • Heating plate (Keurig K-Duo, Ninja DualBrew and DualBrew Pro)
  • High Altitude Settings (Keurig K-Duo, Ninja DualBrew and DualBrew Pro)

Which One Has The Best Additional Features?

The Ninja DualBrew is better than the K-Duo when it comes to additional features. This is mainly because of its independent hot water dispenser, and its “drip stop” feature which works for both pod and carafe brewing.

Additionally, the Ninja DualBrew Pro is even better than the basic model since it comes with an integrated milk frother.

Winner: Ninja DualBrew & DualBrew Pro

Pros and Cons

Here’s a quick summary of the pros and cons of the Keurig K-Duo vs the Ninja DualBrew. Note that we’re only going to highlight the pros and cons that make each machine unique from the other.

Ninja DualBrew Pros and Cons

Here are some pros and cons of the Ninja DualBrew coffee maker.


  • Wide variety of brew sizes
  • Produce really hot coffee (around 170F when brewing pods)
  • Comes with an independent hot water dispenser


  • It is pretty difficult to find reusable pod and mesh filters that are compatible with this machine
  • It causes a lot of dripping if you leave the drip stop open after a brew
  • It beeps constantly and it can be quite annoying

Keurig K-Duo Pros and Cons

Here are some pros and cons of the Keurig K-Duo.


  • Extremely easy to use
  • It’s very easy to find reusable pod and mesh filters for this machine


  • It can be quite annoying to remove the water tank if the machine is placed with its back to a wall
  • The machine is quite bulky


These are some alternatives to the Keurig K-Duo and Ninja DualBrew.

1. Keurig K-Duo Plus

Keurig K-Duo Plus
  • Key Feature: Can brew a carafe
  • Brew Sizes: 6oz, 8oz, 10oz, and 12oz
  • Water Reservoir: 60oz
  • Material: Plastic
  • Brand: Keurig

The Keurig K-Duo Plus is a versatile and convenient coffee maker that can brew both single-serve K-Cups and a full pot of coffee. 

This coffee maker has a few key features that make it unique.

  • 60oz adjustable water tank
  • Slim design that fits almost anywhere
  • 12-cup thermal carafe

This is an excellent alternative to the K-Duo and Ninja DualBrew.

2. Hamilton Beach FlexBrew Trio

Hamilton Beach FlexBrew Trio
  • Key Feature: 2-in-1 design
  • Brew Sizes: 14oz (Single Serve) or 12 Cups (Carafe)
  • Water Reservoir: Two reservoirs, 14oz and 60oz
  • Material: Plastic
  • Brand: Hamilton Beach

The Hamilton Beach FlexBrew Trio is a versatile coffee maker that can brew single-serve pods, and ground coffee.

It features a removable 40oz water reservoir, an adjustable cup rest that accommodates a variety of cup sizes, and the machine has a programmable timer and auto shut-off for added convenience. 

This machine is ideal for those who like the Ninja DualBrew and K-Duo but are looking for a more budget-friendly alternative.

The Bottom Line: Ninja DualBrew vs Keurig K-Duo

Both machines are pretty convenient, but we can conclude that the Ninja DualBrew is the best option between them.

The Keurig K-Duo is an extremely easy-to-use coffee maker that is also very stylish.

On the other hand, the Ninja DualBrew has a wide variety of brew sizes, produces really hot coffee, and has a few additional features that make it the best model.

Also, remember that the Ninja DualBrew Pro has even more features than the DualBrew, so if you find a good deal, don’t doubt to pick that model instead.

Thanks for reading our Ninja DualBrew vs Keurig K-Duo comparison guide. Keep tuned to read more guides like this in the future.

Leandro Santorsola
Leandro Santorsola

Leandro is the founder of The Coffee Arsenal. His favorite relaxation method is to drink a Cafe Latte in the afternoons.