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  1. Home
  2. Blender
  3. Compare
  1. Table of Contents
  2. Top
  3. Main Differences
  4. Design
    1. Dimensions
    2. Build Quality
    3. Jar Capacity
    4. Jar/Beaker Materials
    5. Blades
    6. Lid
    7. Power Cord
    8. In The Box
  5. Performance
    1. Fibrous Ingredients (Small Batches)
    2. Fibrous Ingredients (Full Capacity)
    3. Crushed Ice
    4. Nut Butter
    5. Noise
    6. Blade Speed
  6. Ease Of Use
    1. Controls And Programs
    2. Cleaning
  7. Comments

KitchenAid K400 vs Ninja Blender Duo with Auto-iQ BL642

Side-by-Side Comparison

Products

KitchenAid K400
Ninja Blender Duo with Auto-iQ BL642

Tested using Methodology v1.0

Updated Apr 23, 2025 05:44 PM

SEE PRICE
Amazon.com

Tested using Methodology v1.0

Updated Sep 24, 2024 05:16 PM

SEE PRICE
BestBuy.com
KitchenAid K400 Picture
Ninja Blender Duo with Auto-iQ BL642 Picture
Blender Type
Full Size Blender
Power
1,119 W
Hot Blending
Yes
Blender Type
Full Size Blender
Power
1,200 W
Hot Blending
No

Variants

  • K400 (Almond Cream)
  • K400 (Beetroot)
  • K400 (Blue Velvet)
  • K400 (Blue Velvet W/ Tamper)
  • K400 (Candy Apple)
  • K400 (Contour Silver)
  • K400 (Contour Silver W/ Tamper)
  • K400 (Contour Silver W/ Tamper & Personal Jar)
  • K400 (Dried Rose W/ Tamper)
  • K400 (Matte Black)
  • K400 (Matte Black W/ Tamper)
  • K400 (Matte Black W/ Tamper & Personal Jar)
  • K400 (Milkshake W/ Tamper)
  • K400 (Passion Red)
  • K400 (Passion Red W/ Tamper)
  • K400 (Pistachio W/ Tamper)
  • K400 (White)
  • K400 (White W/ Tamper)
  • BL642 (Black)
  • BL640 (Black)
  • BL641 (Black/Silver)

Review

See KitchenAid K400 Review
See Ninja Blender Duo with Auto-iQ BL642 Review
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Our Verdict

KitchenAid K400

Ninja Blender Duo with Auto-iQ BL642

The KitchenAid K400 is better than the Ninja Blender Duo with Auto-iQ BL642. The KitchenAid makes a smoother blend with fibrous ingredients like kale, especially when you're working with bigger batches, and it can hot blend. It's also easier to clean. On the other hand, the Ninja comes with personal jars and to-go lids for single-serve drinks like smoothies. It's also quieter when it's running.

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Check Price

Almond Cream
K400
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Black
BL642
Searching
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Beetroot
K400
Searching
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Black
BL640
Searching
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Blue Velvet
K400
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Black/Silver
BL641
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Blue Velvet W/ Tamper
K400
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Candy Apple
K400
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Contour Silver
K400
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Contour Silver W/ Tamper
K400
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Contour Silver W/ Tamper & Personal Jar
K400
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Dried Rose W/ Tamper
K400
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Matte Black
K400
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Matte Black W/ Tamper
K400
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Finding store
 
Matte Black W/ Tamper & Personal Jar
K400
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Finding store
 
Milkshake W/ Tamper
K400
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Finding store
 
Passion Red
K400
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Finding store
 
Passion Red W/ Tamper
K400
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Pistachio W/ Tamper
K400
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White
K400
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White W/ Tamper
K400
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Main Differences for
Multi-Purpose

Threshold 

0.10

Multi-Purpose 

8.7
6.9

Hot Blending 
 

Yes
No

Fibrous Ingredients (Full Capacity) 
 

9.7
6.8

Nut Butter 
 

6.9
8.1

Cleaning 
 

7.0
6.0

Full Comparison

Design

Dimensions 
 

Blender Type 
 

Full Size Blender
Full Size Blender

Box Picture  

KitchenAid K400 Box Picture
Ninja Blender Duo with Auto-iQ BL642 Box Picture

Height 
 

15.2" (38.7 cm)
17.8" (45.2 cm)

Width  

7.7" (19.5 cm)
7.6" (19.2 cm)

Depth  

9.2" (23.5 cm)
10.0" (25.5 cm)

Weight 
 

13.0 lbs (5.9 kg)
8.8 lbs (4.0 kg)

Shaft Length (Immersion Blenders) 
 

N/A
N/A
Show Text 

Build Quality 
 

8.0
8.0

Build Quality Picture  

KitchenAid K400 Build Quality Picture
Ninja Blender Duo with Auto-iQ BL642 Build Quality Picture
Show Text 

Jar Capacity 
 

7.8
9.8

Main Jar Capacity 
 

56.0 oz (1,656 ml)
72.0 oz (2,129 ml)

Additional Jar Capacity 
 

N/A
32.0 oz (946 ml)
Show Text 

Jar/Beaker Materials 
 

Jar Picture  

KitchenAid K400 Jar Picture
Ninja Blender Duo with Auto-iQ BL642 Jar Picture

Optional Jar Picture  

KitchenAid K400 Optional Jar Picture
Ninja Blender Duo with Auto-iQ BL642 Optional Jar Picture

Jar/Beaker Material 
 

BPA-Free Plastic
BPA-Free Plastic

Dishwasher Safe 
 

Yes
Yes
Show Text 

Blades 
 

Blades Picture  

KitchenAid K400 Blades Picture
Ninja Blender Duo with Auto-iQ BL642 Blades Picture

Blade Type 
 

Sharp
Sharp

Blade Count 
 

4
6

Removable 
 

No
Yes

Dishwasher Safe 
 

Yes
Yes
Show Text 

Lid 
 

Lid Picture  

KitchenAid K400 Lid Picture
Ninja Blender Duo with Auto-iQ BL642 Lid Picture

Two-Part Lid 
 

Yes
No

Lid Closing Type 
 

Friction
Lock Mechanism
Show Text 

Power Cord  

Cable Picture  

KitchenAid K400 Cable Picture
Ninja Blender Duo with Auto-iQ BL642 Cable Picture

Stow-Away Compartment 
 

No
Yes

Cord Length 
 

3.0 ft (0.9 m)
2.6 ft (0.8 m)
Show Text 

In The Box  

Bundle Picture  

KitchenAid K400 Bundle Picture
Ninja Blender Duo with Auto-iQ BL642 Bundle Picture
Show Text 
Performance

Fibrous Ingredients (Small Batches) 
 

9.7
9.3

Fibrous Ingredients (Small Batches) Photo  

KitchenAid K400 Fibrous Ingredients (Small Batches) Photo
Ninja Blender Duo with Auto-iQ BL642 Fibrous Ingredients (Small Batches) Photo

Jar Used 
 

Main Jar
Additional Jar

Fibrous Ingredients (Small Batches) Video  

Fibrous Ingredients Processing 
 

8.5
8.5

Fibrous Ingredients Texture 
 

10
9.5
Show Text 

Fibrous Ingredients (Full Capacity) 
 

9.7
6.8

Fibrous Ingredients (Full Capacity) Photo  

KitchenAid K400 Fibrous Ingredients (Full Capacity) Photo
Ninja Blender Duo with Auto-iQ BL642 Fibrous Ingredients (Full Capacity) Photo

Fibrous Ingredients (Full Capacity) Video  

Jar Used  

Main Jar
Main Jar

Fibrous Ingredients Processing 
 

8.5
6.0

Fibrous Ingredients Texture 
 

10
7.0
Show Text 

Crushed Ice 
 

9.7
10

Crushed Ice Photo  

KitchenAid K400 Crushed Ice Photo
Ninja Blender Duo with Auto-iQ BL642 Crushed Ice Photo

Crushed Ice Video  

Crushed Ice Preparation 
 

9.0
10

Crushed Ice Texture 
 

10
10
Show Text 

Nut Butter 
 

6.9
8.1

Nut Butter Picture  

KitchenAid K400 Nut Butter Picture
Ninja Blender Duo with Auto-iQ BL642 Nut Butter Picture

Nut Butter Video  

Nut Butter Preparation 
 

3.0
6.0

Nut Butter Texture 
 

9.5
9.5
Show Text 

Noise 
 

6.8
7.4

Noise @ Max Speed 
 

94.8 dB
91.4 dB

Noise Video  

Show Text 

Blade Speed 
 

Min Speed 
 

3,200 RPM
3,200 RPM

Power 
 

1,119 W
1,200 W

Max Speed 
 

16,000 RPM
4,600 RPM

Speed Adjustment Based On Jar Type 
 

No
Yes
Show Text 
Ease Of Use

Controls And Programs 
 

Control Panel  

KitchenAid K400 Control Panel
Ninja Blender Duo with Auto-iQ BL642 Control Panel

On/Off Switch 
 

No
Yes

Speed Presets 
 

0
3

Hot Blending 
 

Yes
No

Speed Dial 
 

Yes
No

Pulse/Turbo Mode 
 

Yes
Yes

Programs 
 

4
4

Blending Time Indicator 
 

No
Yes

Programmable Timer 
 

No
No
Show Text 

Cleaning 
 

7.0
6.0

Self-Cleaning Video  

Cleaning Video  

Show Text 

Check Price

Almond Cream
K400
Searching
Finding store
Black
BL642
Searching
Finding store
Beetroot
K400
Searching
Finding store
Black
BL640
Searching
Finding store
Blue Velvet
K400
Searching
Finding store
Black/Silver
BL641
Searching
Finding store
Blue Velvet W/ Tamper
K400
Searching
Finding store
 
Candy Apple
K400
Searching
Finding store
 
Contour Silver
K400
Searching
Finding store
 
Contour Silver W/ Tamper
K400
Searching
Finding store
 
Contour Silver W/ Tamper & Personal Jar
K400
Searching
Finding store
 
Dried Rose W/ Tamper
K400
Searching
Finding store
 
Matte Black
K400
Searching
Finding store
 
Matte Black W/ Tamper
K400
Searching
Finding store
 
Matte Black W/ Tamper & Personal Jar
K400
Searching
Finding store
 
Milkshake W/ Tamper
K400
Searching
Finding store
 
Passion Red
K400
Searching
Finding store
 
Passion Red W/ Tamper
K400
Searching
Finding store
 
Pistachio W/ Tamper
K400
Searching
Finding store
 
White
K400
Searching
Finding store
 
White W/ Tamper
K400
Searching
Finding store
 
Back to Top

KitchenAid K400

Ninja Blender Duo with Auto-iQ BL642

Comments

  1. Comparison
 • Posted 1 year ago

KitchenAid K400 vs Ninja Blender Duo with Auto-iQ BL642: Main Discussion

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