iRobot Roomba S9 vs Roomba i3

Which Robot Vacuum Is Better?

Products

iRobot Roomba S9
iRobot Roomba i3

Tested using Methodology v1.0

Updated Aug 27, 2025 02:57 PM

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iRobot

Tested using Methodology v1.0

Updated Aug 27, 2025 03:00 PM

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Amazon.com
  1. Recommended in 1 article:
  2. iRobot
  1. Recommended in 1 article:
  2. iRobot

Our Verdict

iRobot Roomba S9

iRobot Roomba i3

The iRobot Roomba S9 is better than the iRobot Roomba i3. The S9 is better built, incurs fewer recurring costs, has a longer battery life, maneuvers itself more effectively, and performs better on all surface types. Meanwhile, the i3 has a self-emptying function, though it's worth noting that this feature is also available for the S9 at an additional cost.

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Variants

  • Roomba S9 (Black)
  • Roomba S9+ (Black)
  • Roomba i3+ EVO (Woven Neutral)
  • Roomba i3 EVO (Woven Neutral)

Check Price

Black
Roomba S9
Amazon.com
Woven Neutral
Roomba i3+ EVO
SEE PRICE
Amazon.com
Black
Roomba S9+
SEE PRICE
iRobot
Woven Neutral
Roomba i3 EVO
SEE PRICE
Amazon.com

Main Differences for
Multi-Surface Household

Threshold 

0.10

Multi-Surface Household 
 

6.4
6.4

Hard Floor Pickup 
 

8.5
6.5

Station Maintenance Capabilities 
 

0.0
6.4

Full Comparison

Design

Build Quality 
 

8.5
8.0

Build Quality Picture 
 

Compare High-Res
iRobot Roomba S9 Build Quality Picture
Compare High-Res
iRobot Roomba i3 Build Quality Picture

Vacuum & Mop Combo 
 

No
No
Show Text 

User Maintenance 
 

7.5
7.5

Maintenance Picture 
 

Compare High-Res
iRobot Roomba S9 Maintenance Picture
Compare High-Res
iRobot Roomba i3 Maintenance Picture

Brushroll Cleaning Video  

Show Text 

Recurring Cost 
 

4.5
3.0

Recurring Cost Picture 
 

Compare High-Res
iRobot Roomba S9 Recurring Cost Picture
Compare High-Res
iRobot Roomba i3 Recurring Cost Picture

Bag Part Number  

No bag
4640235

Filter Part Number  

4643682
4639161

HEPA Filter Part Number  

4643682
4639161
Show Text 

Dimensions 
 

Robot Vacuum Dimensions 
 

Compare High-Res
iRobot Roomba S9 Robot Vacuum Dimensions
Compare High-Res
iRobot Roomba i3 Robot Vacuum Dimensions

Robot Vacuum Height  

9.6 cm (3.8")
9.4 cm (3.7")

Robot Vacuum Width  

31.6 cm (12.4")
33.9 cm (13.3")

Robot Vacuum Depth  

31.6 cm (12.4")
34.3 cm (13.5")

Docking Station Dimensions 
 

Compare High-Res
iRobot Roomba S9 Docking Station Dimensions
Compare High-Res
iRobot Roomba i3 Docking Station Dimensions

Docking Station Height  

10.7 cm (4.2")
48.4 cm (19.1")

Docking Station Width  

25.9 cm (10.2")
31.1 cm (12.2")

Docking Station Depth  

36.0 cm (14.2")
38.9 cm (15.3")
Show Text 

Internal Dirt Compartment 
 

8.1
6.1

Dirt Compartment Photo 
 

Compare High-Res
iRobot Roomba S9 Dirt Compartment Photo
Compare High-Res
iRobot Roomba i3 Dirt Compartment Photo

Dirt Compartment Capacity 
 

0.50 L
0.25 L

Full Indicator 
 

Yes
Yes
Show Text 

Station Maintenance Capabilities 
 

0.0
6.4

Station Photo 
 

Compare High-Res
iRobot Roomba S9 Station Photo
Compare High-Res
iRobot Roomba i3 Station Photo

Auto Empty 
 

No
Yes

Bagless Station 
 

No Dirt Compartment
No

Dirt Compartment Capacity 
 

0.00 L
2.40 L

Automatic Tank Refill 
 

No
No

Mop Washing 
 

No
No

Mop Drying 
 

No
No
Show Text 

In The Box 
 

In The Box Picture 
 

Compare High-Res
iRobot Roomba S9 In The Box Picture
Compare High-Res
iRobot Roomba i3 In The Box Picture
Show Text 

Battery 
 

9.2
8.9

Minimum Battery Life 
 

49 min
87 min

Maximum Battery Life 
 

155 min
87 min

Recharge Time 
 

92 min
94 min

Removable Batteries 
 

Yes
Yes
Show Text 

Quality-Of-Life Features 
 

Picture Of Controls 
 

Compare High-Res
iRobot Roomba S9 Picture Of Controls
Compare High-Res
iRobot Roomba i3 Picture Of Controls

Power Adjustment 
 

Yes
No

Easy On/Off 
 

Yes
Yes

Surface Type Adjustment 
 

Only Automatic
Only Automatic
Show Text 

Brushroll And Tools 
 

Brushroll And Tools Photo 
 

Compare High-Res
iRobot Roomba S9 Brushroll And Tools Photo
Compare High-Res
iRobot Roomba i3 Brushroll And Tools Photo

Brushroll Setup 
 

Dual
Dual

Brushroll Type 
 

Rubber
Rubber

Side Brush Setup 
 

Single
Single

Side Brush Type 
 

Fixed
Fixed
Performance

Hard Floor Pickup 
 

8.5
6.5

Hard Floor Pickup Video  

Hard Floor Pickup Post Test 
 

Compare High-Res
iRobot Roomba S9 Hard Floor Pickup Post Test
Compare High-Res
iRobot Roomba i3 Hard Floor Pickup Post Test
Show Text 

High-Pile Carpet Pickup 
 

8.0
7.5

High-Pile Carpet Pickup Video  

High-Pile Carpet Pickup Post Test 
 

Compare High-Res
iRobot Roomba S9 High-Pile Carpet Pickup Post Test
Compare High-Res
iRobot Roomba i3 High-Pile Carpet Pickup Post Test
Show Text 

Low-Pile Carpet Pickup 
 

7.5
7.0

Low-Pile Carpet Pickup Video  

Low-Pile Carpet Pickup Post Test 
 

Compare High-Res
iRobot Roomba S9 Low-Pile Carpet Pickup Post Test
Compare High-Res
iRobot Roomba i3 Low-Pile Carpet Pickup Post Test
Show Text 

Pet Hair Pickup 
 

7.5
8.0

Pet Hair Pickup Video  

Pet Hair Pickup Post Test 
 

Compare High-Res
iRobot Roomba S9 Pet Hair Pickup Post Test
Compare High-Res
iRobot Roomba i3 Pet Hair Pickup Post Test
Show Text 

Airflow 
 

8.2
5.7

Maximum Airflow Video  

Maximum Head Airflow 
 

16.0 CFM (0.5 m³/min)
5.8 CFM (0.2 m³/min)
Show Text 

Noise 
 

7.0
7.6

Noise Video 
 

Bare Floor 
 

65.2 dBA
63.8 dBA

Low-Pile Carpet 
 

64.7 dBA
59.5 dBA
Show Text 

Household Adaptability 
 

7.0
8.0

Household Adaptability  

Show Text 

Obstacle Avoidance 
 

2.0
3.5

Obstacle Avoidance Technology 
 

Light-Based
Light-Based

Object Recognition 
 

No
No

Obstacle Video  

Bare Floor: Avoidance Rate 
 

0%
0%

Bare Floor: Intervention Rate 
 

40%
20%

Carpet: Avoidance Rate 
 

0%
0%

Carpet: Intervention Rate 
 

42%
25%

Always Avoided Pet Waste 
 

No
No

Height Clearance 
 

7.0
7.0

Height Clearance Video  

Lowest Height Cleared 
 

9.5 cm (3.7'')
9.5 cm (3.7'')

Threshold Clearance 
 

7.0
7.0

Low Threshold Video  

High Threshold Video  

Max Threshold Height 
 

1.9 cm (0.7")
1.9 cm (0.7")

Air Quality 
 

Sealing Quality Video  

Anti-Allergy Filter (HEPA) 
 

Yes
Yes
Show Text 

Cracks 
 

4.5
4.5

Cracks Video  

Wood Cracks Post Test 
 

Compare High-Res
iRobot Roomba S9 Wood Cracks Post Test
Compare High-Res
iRobot Roomba i3 Wood Cracks Post Test
Show Text 

Stains 
 

1.0
1.0

Stain Video  

Stain Pickup Post Test 
 

Compare High-Res
iRobot Roomba S9 Stain Pickup Post Test
Compare High-Res
iRobot Roomba i3 Stain Pickup Post Test
Show Text 

Water 
 

0.0
0.0

Wet Compatible 
 

No
No

Water Video  

Water Pickup Post Test 
 

Compare High-Res
iRobot Roomba S9 Water Pickup Post Test
Compare High-Res
iRobot Roomba i3 Water Pickup Post Test
Show Text 
Automation

Physical Automation 
 

8.9
8.9

Recharge And Resume 
 

Yes
Yes

Pathing Algorithm 
 

Smart
Smart

Physical Boundary Markers 
 

No
No

Scheduled Start Buttons 
 

No
No

Cycle Control Buttons 
 

On-Board Only
On-Board Only

Navigation Control Buttons 
 

Return To Base Only
Return To Base Only
Show Text 

Companion App Automation 
 

8.0
8.0

Companion App Screen Grabs 
 

Compare High-Res
iRobot Roomba S9 Companion App Screen Grabs
Compare High-Res
iRobot Roomba i3 Companion App Screen Grabs

App Name 
 

iRobot HOME
iRobot HOME

Software Boundary Markers (No-Go Zones) 
 

Yes
No

App Scheduled Start 
 

Yes
Yes

App Cycle Control 
 

Yes
Yes

Navigation Control Within App 
 

No
No
Show Text 
To Be Deleted

Check Price

Black
Roomba S9
Amazon.com
Woven Neutral
Roomba i3+ EVO
SEE PRICE
Amazon.com
Black
Roomba S9+
SEE PRICE
iRobot
Woven Neutral
Roomba i3 EVO
SEE PRICE
Amazon.com

iRobot Roomba S9

iRobot Roomba i3

Comments

  1. Comparison

iRobot Roomba S9 vs iRobot Roomba i3: Main Discussion

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