The Ninja DUO is a full-size blender that comes in several variants with different beakers and attachments. Our test unit comes with a micro-juicer attachment which allows you to more finely process juice, although we don't currently test this. This well-built blender also produces silky smoothies and almond butter as well as bar-quality ice. Its jars, blade assemblies, and lids can go into a dishwasher's top rack for an easy clean. However, it shouldn't be used to blend hot food as it uses a vacuum-seal lid without an opening. It's also very loud at max speed.
Note 11/06/2020: We've updated this blender's advertised wattage, but the scoring of the review hasn't changed.
The Ninja DUO blender is alright for multi-purpose uses. This well-built blender can easily make silky smoothies and almond butter. It's also able to process bar-quality ice in half a minute, which is outstanding for making slushy drinks. However, as it uses a vacuum-seal lid, it shouldn't be used for blending hot food as there's nowhere for steam to escape. There are also many places food debris can get into, making cleaning it a bit more difficult. Luckily, you can throw its jars, blades, and lids into your dishwasher's top rack.
The Ninja DUO blender is great for making smoothies. It has a dedicated 'Smoothie Mode' preset, which produces silky smoothies that remain cold after being blended when using frozen ingredients. This well-built blender can crush ice very easily as well, so you won't have big chunks left in your drink.
The Ninja DUO blender is outstanding at crushing ice. It can easily make bar-quality ice in half a minute when using its 'Frozen Drink' preset. This blender is also well-built and sturdy.
The Ninja DUO blender isn't recommended for blending hot food as its vacuum-seal lid doesn't have an air vent to allow steam to escape.
The Ninja DUO blender is excellent for professional use. Although it's made from plastic, it has a robust and sturdy build. It can process almonds into nut butter very well, and it produces bar-quality ice quickly. Its main jar can also hold a lot of food, which is handy if you're making a lot of something. However, its max speed is very loud.
Although it's slightly smaller than the Ninja Mega Kitchen System BL770, the Ninja DUO is a fairly bulky blender. If you want to store it on your counter or in a cupboard, you need to make sure you have room for it.
The Ninja DUO has a great build quality. Although most of the blender, including the transmission gear, is made from cheap-feeling plastic, it still seems pretty solid. The main blending jar also has sturdy metal blades fixed directly to the bottom of the jar. While the blades can't be removed for easier cleaning by hand, the combined jar and blade assembly can be washed is top-rack dishwasher safe.
On the downside, the main container doesn't seem to be shatter-proof and it could crack if you drop it. Water and other liquid can also get stuck in places such as inside the main jar's handle or inside the vacuum seal area of both the main and additional jar, which is a little annoying.
The main container has a large capacity and is capable of holding a lot of liquid. It also has a spout so that you can easily serve food directly from your jar. The container, lid, and blade assembly are all dishwasher safe as long as you separate the lid from the jar. They go into your dishwasher's top rack.
The Ninja DUO blender comes with two additional jars which are great for taking smoothies with you on-the-go. These jars, their lids, and blade assemblies are also dishwasher-safe as long as you remove the lid from the cup. You can put these pieces in the dishwasher's top rack for cleaning.
The Ninja DUO blender has sharp blades. While they're attached to the bottom of the jar and can't be removed, you can put them into the dishwasher's top rack as long as you separate the lid from the jar.
Update 11/06/2020: We've updated the blade count from 6 to 8.
This lid locks into place to keep your food from spilling out of the jar. It has a vacuum seal release as well as a section of the lid that needs to be opened to fully clean this part.
The power cord is long enough to reach an outlet on your counter. When not in use, the blender has a stowaway compartment for the cable.
The Ninja DUO has several preset speeds to better process different kinds of food. It's extremely loud at its max speed though. For a blender that's quieter at max speed, check out the Ninja Professional Plus Kitchen System with Auto-iQ.
Update 11/06/2020: We've retested the noise at max speed and have updated our test results.
The Ninja DUO blender is great at making almond butter. While it produces pretty smooth almond butter, it's not really sticky and there are still some small chunks of almonds that aren't fully processed. It can crush almonds, but it doesn't reincorporate them back into the mix as they cling to the sides of the jar. You may need to stop the blender to push everything back into the blade's path. If you're looking for a full-size Ninja blender that can make smooth almond butter in less time, consider the Ninja Foodi Power Pitcher System.
When using the main jar, the Ninja DUO blender makes excellent smoothies. Although the vacuum seal takes between 30-50 seconds to fully seal, once it's ready to use, it's able to make a smooth blend on its 'Smoothie Mode' in about a minute. The resulting smoothie is silky, and it remains very cold. There are small pieces of kale left over, but it shouldn't be too noticeable.
The Ninja DUO's additional jars are also outstanding for making smoothies. While the container's vacuum seal can take 30-50 seconds to fully set, it takes about a minute to produce a smoothie. It's extremely similar in quality to the main jar's final product, but it has slightly more foam. It also does a marginally better job of processing kale into smaller pieces than the main jar.
The ice crushing performance of the Ninja DUO blender is outstanding. When using the frozen drink preset, you can easily get bar-quality ice in about half a minute.
This blender has several modes: 'Extract', 'Smoothie', 'Juice', 'Frozen Drink', 'Puree', 'Ice Cream', 'Dressing', 'Pulse', 'Low', 'High', and 'Drinksaver/Store (vacuum)'. It also has a timer so you know how much time is left when using each of the modes. If you want a blender with dedicated crushed ice and self-clean programs, check out the Breville the Q.
The Ninja DUO is somewhat easy to clean. While liquidy foods like smoothies can be easily rinsed from the jar, pieces of kale can get stuck in the additional jar's vacuum seal tube. This part also uses two screws to hold the vacuum chamber together, and you need to use a screwdriver to thoroughly clean it. If you're blending more sticky food like almond butter, it can get stuck underneath the blade, and you need a special brush to reach this spot to clean it. Even if you soak the jar with water and soap, its sides remain pretty greasy, and you need to scrub it down with soap to clean it. That being said, the jars, blade assemblies, and lids can all go into your dishwasher's top rack for cleaning, although it still may not get them completely clean. If you want a blender that's easier to hand wash, consider the NutriBullet PRO 1000 or the Ninja Professional Plus Blender with Auto-iQ.
This blender doesn't have a lot of extra features. Unlike the Blendtec Classic 575, it has a juicer attachment that allows you to strain more food pieces so you get an even smoother final product. There's also a vacuum pump, which is advertised to produce brighter flavors with a better texture. The vacuum pump could help produce a more flavorful final product, but we don't currently test this. However, unlike the Hamilton Beach Power Elite Multi-Function, it can't hot blend.
The Ninja DUO comes in three variants that have different combinations of additional features. We tested one version of the IV107 variant, which comes fully loaded and has two 20 oz beakers included. However, the IV107 normally only comes with only one 20 oz beaker.
|Ninja DUO IV107 (2 beakers included)||NINJA DUO IV107||Ninja DUO BL641C|
1x Motor base
1x Motor base
1x Motor base
|Personal Jar||2x 20 oz beaker||1x 20 oz beaker||1x 24 oz beaker
1x 32 oz beaker
1x Micro-juicer attachment
The Ninja DUO is a well-built full-size blender geared towards making smoothies, especially as there's a variant of it with a micro-juicer attachment. When compared to other smoothie blenders like the NutriBullet Blender Combo, it does a better job of quickly blending tough foods into a silky consistency. However, if you're looking for a multi-purpose blender, note that just like the Ninja Mega Kitchen System BL770, it can't blend hot food safely as its lid doesn't have an opening to let steam out.
The Ninja Blender Duo with Auto-iQ BL642 is better for most purposes than the Ninja DUO. The Blender Duo with Auto-iQ makes smoother, more spreadable almond butter and a silkier smoothie in its 32-ounce personal jar. It also makes crushed ice with a better texture. However, the DUO comes with more extra features, including a juicer attachment and a vacuum pump, although we don't test them currently.
The Ninja DUO is a better full-size blender than the Ninja Professional Plus Blender with Auto-iQ. The DUO comes with two additional 20-ounce beakers, more preset modes, and a timer, unlike the Professional Plus. It also makes a better, more spreadable almond butter and a better-blended smoothie. That said, the Professional Plus is easier to clean.
The Ninja Foodi Power Nutri DUO is better than the Ninja DUO for most purposes. The Nutri DUO is a personal blender that makes more spreadable almond butter, better-blended smoothies, and crushed ice with a better texture. It's also easier to clean by hand. However, the DUO is a full-size blender that comes with a 72-ounce pitcher in addition to a pair of personal jars. There's also a juicer attachment included, although we don't currently test it.
The Vitamix Explorian E310 is a better blender for making smoothies than the Ninja DUO. The Vitamix has a significantly better build quality, and it produces silkier almond butter and smoothies in less time. Cleaning this blender is also much simpler, and you can even safely blend hot foods with it. However, the Ninja comes with a personal jar that some may prefer.
The Ninja DUO is a better blender for making smoothies than the Blendtec Classic 575. The Ninja makes silky smoothies in less time, can produce smoother almond butter, and its crushed ice is fine and snow-like. It also comes with a personal blending jar, so you can quickly take your blend with you on the go. However, if you're looking for something more versatile, the Blendtec is better-built, can process hot food, and it's way easier to clean messes from it. It also comes in several bright colors to better suit your kitchen decor.
The Ninja DUO is better for making smoothies than the NutriBullet Blender Combo. The Ninja can produce silkier smoothies in less time, and you can pick up a variant with a micro-juicing attachment. It's also better at making almond butter. However, it's loud when blending. The NutriBullet, in comparison, has fewer cleaning needs, and it can make snow-like ice.
The Ninja Mega Kitchen System BL770 is better than the Ninja DUO. The BL770 makes much better-blended smoothies and almond butter. It also makes crushed ice with a better texture, comes with a food processing attachment, and is much easier to clean by hand. However, the DUO comes with a juicer attachment and a personal jar with a vacuum pump intended to help keep blends fresh.
The Ninja DUO is a better full-size blender than the Hamilton Beach Power Elite Multi-Function. The Ninja outperforms the Hamilton Beach in pretty much every way as it has a better build quality, comes with a personal jar, and offers more speed settings. It can also make almond butter, silky smoothies, and bar-quality crushed ice. However, the Hamilton Beach is easier to clean.
The Ninja DUO and the Ninja Professional Plus Kitchen System with Auto-iQ are very similar blenders, and depending on your usage habits, you may prefer one over the other. Both come with two personal-sized additional jars, but the DUO's are each 20 ounces while the Professional Plus' are each 24 ounces. The Professional Plus comes with a food processor, while the DUO comes with a microjuicer attachment and a vacuum pump. The DUO is better for almond butter, and its main jar makes a better smoothie. However, the Professional Plus isn't as loud, and it's easier to hand wash.
The Ninja DUO is better than the NutriBullet Pro for most purposes. The Ninja is full-size blender that comes with a 72-ounce main jar as well as a pair of smaller personal jars. It has a much better build quality, can crush ice, and does a much better job of making almond butter. There's also a juicer attachment included, although we don't test it currently. However, the NutriBullet is a more compact personal blender that makes significantly better-blended smoothies.
The Ninja DUO is a better overall blender than the NutriBullet PRO 1000. The Ninja is a full-size blender with a 20-oz personal jar, so it's a better choice for larger batches. It's better-built, and it comes with more features, including preset modes, a pulse mode, a timer, and a juicer attachment. The Ninja can make smooth, spreadable almond butter and a more drinkable smoothie, and it crushes ice in less time. That said, the personal-size NutriBullet is easier to hand wash.
The Ninja DUO is a better blender for making smoothies than the Ninja Foodi Cold & Hot Blender. The DUO can make silky smoothies, it comes with a personal jar so you can take your drink with you on the go, and there's even a variant with a micro-juicer attachment available. It can also make snow-like ice. However, the Foodi is better if you're looking for something more versatile. It's better built, significantly easier to clean, and it can produce smooth almond butter in less time.
The Ninja Foodi Power Pitcher System is a better full-sized blender than the Ninja DUO. The Foodi Power Pitcher System comes with three jars, including one that has manually rotating arms to help get food stuck on the jar's sides back into the blade's vortex, and it's easier to clean. It has a speed dial, and it can make better almond butter and smoothies with its jars. However, the DUO comes with a juicer attachment as well as a vacuum pump.
The Breville The Q is a better blender than the Ninja DUO for most uses. The Breville makes a better smoothie, and it's much easier to clean by hand. It also comes with an ice crush and self-clean modes, which the Ninja lacks. However, the Ninja does a better job crushing ice, and it comes with two additional personal jars.