Dreame L40s Ultra
Rank 39 of 64 robots with an all-in-one station in our ranking, tested by Vacuum Wars.in our ranking, tested by Vacuum Wars ★ 4.0 · 271 reviews
Score 6.6 out of 10
Lab tests, 60% of the score: 6.7, measured by Vacuum Wars.
Owners’ ratings, 25%: 5.1, from 271 ratings averaging 4.0 stars at Amazon.
Features, 15%: 8.6, 79 of the 92 points for the facts the maker states.
Price does not count, so a discount never lifts a model. Only robots a lab has tested are ranked.
The highest score today is 7.6.
- Long hair anti-tangle brush
- Water hookup dock connects to the water supply
Prices per store
On September 29, 2026 the lowest price for the Dreame L40s Ultra is $484 at Amazon.com, shipping to the United States included. In our ranking it is rank 39 of 64 with an all-in-one station, with a score of 6.6 out of 10.
All prices include shipping to the United States. Sales tax is added at checkout. We may earn a commission when you buy through these links. It never changes our ranking.
| Store | Color | Price | Delivery time and returns | Reviews | Checked | Link to the store |
|---|---|---|---|---|---|---|
 Amazon.com whitelowest price | white | $484lowest price since Sep 1: $484 | about 1–5 dayslowest price | ★ 4.0 (271) | 6 hours ago | Visit store ↗ |
Price history
What the tests like and dislike about the Dreame L40s Ultra
Pros
- Among the strongest robots tested at deep cleaning carpet Vacuum Wars ↗
- Dual rubber brush kept long hair completely untangled Vacuum Wars ↗
- Extending side brush clearly improved dirt removal from corners Vacuum Wars ↗
Cons
- Among the weakest scores on record at avoiding obstacles Vacuum Wars ↗
- Cheaper AE version avoids obstacles far better and scored higher overall Vacuum Wars ↗
- Advertised threshold climbing is nothing special, many robots cross the same Vacuum Wars ↗
Each point sums up, in our words, the review of the test it names, and its link leads to that review. We do not summarize RTINGS or Wirecutter: their lists are linked above.
Dreame L40s Ultra specifications
The numbers that matter first, then every fact by group. As published by the maker or the store we read it from.
Consumables: a 3.2 l dust bag in the station, which lasts up to 100 days.
Suction and brushes 3 facts
- Suction power
Suction in pascal, as the maker measures it. More pascal helps on carpet, but it says little about how well the robot picks grit off a hard floor.
- 19,000 Pa
- Anti-tangle brush
A brush that guides hair to the side instead of letting it wind around the shaft. It saves the cutting work in homes with long hair or pets.
- yes
- Extending side brush
The side brush swings out in a corner or along a baseboard, so the dust there is swept in too.
- yes
Mopping 4 facts
- Mop type
How the mop is built: flat pads, two spinning discs or a roller. Discs press harder on dried-on dirt, a roller rinses itself while it works.
- spinning pads
- Mop lift on carpet
How far the robot lifts the mop when it drives onto a carpet. From about 0.4 in (10 mm) a medium pile stays dry.
- 0.4 in (10.5 mm)
- Mop extends to the edges
The pad slides out along a wall or a baseboard, so the last few inches are mopped as well.
- yes
- Automatic mop detach
The robot leaves the mop at the dock before it vacuums a carpet, so the carpet never gets wet.
- yes
Dock 12 facts
- Empties the dust bin
The dock empties the robot’s dust bin, usually after every run. You only empty the dock’s bag or bin.
- yes
- Bagless
The dock collects dust in a bin instead of a disposable bag. No bags to buy, but you empty it yourself.
- no
- Dust bag capacity
How much the dust bag in the dock holds.
- 3.2 l
- Dust bag lasts
How long the maker says a dust bag lasts with daily use. With pets or a lot of carpet it is shorter.
- up to 100 days
- Washes the mop
The dock washes the mop for you, so you do not rinse it by hand.
- yes
- Wash temperature
How hot the dock washes the mop. Above 140 °F (60 °C) grease comes off, which is what keeps a mop from smelling.
- 167 °F (75 °C)
- Dries the mop
The dock dries the mop afterwards, so it does not sit there wet and start to smell.
- yes
- Hot-air drying
Drying is done with warm air instead of cold. It is faster and it helps against smell.
- yes
- Dispenses detergent
The dock mixes detergent into the water itself, from its own bottle.
- yes
- Plumbing hookup
The dock can be connected to the tap and the drain, so you never fill or empty a tank. It does need a connection nearby.
- yes
- Clean water tank
The clean water tank in the dock, which wets the mop.
- 4.5 l
- Dirty water tank
The tank that catches the dirty water from the mop. You empty this one yourself.
- 4 l
Navigation and obstacles 3 facts
- Navigation
How the robot maps your home and follows that map. Lidar measures with a laser and works in the dark, a camera looks along and recognizes more.
- LiDAR turret
- Obstacle avoidance
How the robot sees loose things on the floor, such as cables, socks or a pet accident. A camera with depth sensing sees more than a bumper that reacts on contact.
- 3D sensor (structured light)
- Climbs thresholds up to
The highest threshold the robot takes, as the maker states it. Measure your own: the step into a bathroom or onto a balcony is often higher.
- 0.9 in (22 mm)
Robot 2 facts
- Robot height
How tall the robot is. It decides whether it fits under your sofa, bed or cabinet.
- 3.8 in (9.7 cm)
- Dust bin in the robot
How much dust the robot holds before you empty it. It matters less with a self-emptying dock, which empties the bin after every run.
- 310 ml
Battery 2 facts
- Battery capacity
The capacity of the battery. It hints at the runtime, but how much the robot draws counts just as much.
- 5,200 mAh
- Runtime per charge
How long the robot cleans on one charge, at its quietest setting. After that it recharges and carries on where it stopped.
- 220 min
Sources: dreametech.com
Our score
Score 6.6 out of 10
Confidence: medium. One lab and fewer than 300 owners’ ratings.
- Lab tests 60% 6.7 Lab tests, 60% of the score: 6.7, measured by Vacuum Wars.
- Owners’ ratings 25% 5.1 Owners’ ratings, 25%: 5.1, from 271 ratings averaging 4.0 stars at Amazon.
- Features 15% 8.6 Features, 15%: 8.6, 79 of the 92 points for the facts the maker states.
Measured 6.7, counted 6.7: the fewer labs stand behind a result, the more we pull it toward the average of its station type.
What the lab measured
- Deep clean on carpet 8.4
- Pet hair 7.9
- Mopping 6.5
- Obstacle avoidance 2.1
- Navigation 7.2
- Vacuum Wars · the testread on September 29, 2026
Price does not count, so a discount never lifts a model. Only robots a lab has tested are ranked. How we work this out.
The testers’ picks
- Vacuum Wars · Position 40 of 151September 26, 2026
Positions and labels, never text. These picks are shown beside the score and do not count in it. How the score comes about is on the method page.
