Introduction
The Dreame X40 Ultra and the Dreame X50s Ultra represent two distinct technological generations within this brand's premium range. The first model arrived on the market in 2024, whilst the X50s Ultra was released in May 2026, incorporating significant advances that mark a clear evolution in performance. Both units feature a complete multifunction base, which guarantees automatic maintenance of the robot without constant user intervention.
These are robots designed for those seeking maximum automation in home cleaning. The generational difference is particularly noticeable in suction power, navigation and mopping capabilities, aspects where the more recent model introduces substantial improvements.
Power and Suction
The most striking difference between these models lies in suction power. The Dreame X40 Ultra reaches 12,000 Pa, a more than respectable figure for most domestic surfaces. However, the X50s Ultra multiplies this capacity up to 35,000 Pa, a power that far exceeds what is usual on the market and which is especially useful on long-pile carpets or for homes with pets that shed a lot of hair.
The brushing system also undergoes a notable evolution. Whilst the X40 Ultra features a conventional single brush, the X50s Ultra incorporates the dual HyperStream brush, designed specifically to reduce hair tangles. This system uses two brushes anchored at one end that facilitate direct suction without hairs becoming trapped in the main roller.
Both robots raise the main brush during mopping and feature an extendable, liftable and anti-tangle side brush. This means they can adapt to different cleaning situations without dragging dirt or damaging the mops during mopping. In practice, these functions allow the robot to alternate between vacuuming and mopping without the need for manual intervention.
Mopping
Both units use the system of two rotating mops with edge extension and Roboswing movement, which allows the mops to reach slightly under ledges and furniture. Mop lifting reaches 10.5 mm in both cases, sufficient to prevent medium-thickness carpets from getting wet during selective mopping.
The major difference lies in the mopping water temperature. The Dreame X40 Ultra mops with cold water, whilst the X50s Ultra incorporates hot water at 45°C. This feature significantly improves the removal of stuck-on stains and grease, especially in kitchens or high-traffic areas. Hot water also contributes to deeper sanitisation of the floor.
Both models automatically remove the mops at the base when they only need to vacuum, and feature dirt detection both on the mops and on the floor. This means the robot can automatically go over particularly dirty areas without us having to programme it manually.
Navigation System
The Dreame X40 Ultra uses a traditional 3D LiDAR turret, which protrudes slightly from the robot's upper surface. The X50s Ultra makes a qualitative leap with a retractable LiDAR that hides when not needed, contributing to reducing the unit's overall height.
The difference in obstacle recognition is substantial: 120 identifiable objects versus 280. The more recent model also incorporates improved lighting for obstacle avoidance and dual RGB cameras that offer greater precision in environmental recognition. This translates into fewer manual interventions and greater real autonomy of the robot.
Both units include a front 3D laser sensor, night vision LED, pet and curtain recognition, as well as remote camera access. The CleanGenius AI system is present in both, although the X50s Ultra version presumably incorporates improvements derived from its greater processing capacity.
Autonomy and Battery
Battery capacity is identical: 6,400 mAh in both robots. The X40 Ultra offers a declared autonomy of 194 minutes, a figure that is not available for the more recent model. In practice, this capacity is sufficient for homes of up to 200-250 square metres in a single cycle, depending on the type of cleaning and obstacles present.
It's worth bearing in mind that the X50s Ultra's greater suction power could slightly affect real autonomy in maximum mode, although the 6,400 mAh battery more than compensates for this additional consumption.
Smart Functions
The Dreame X40 Ultra can overcome thresholds of up to 22 mm, a useful capability for navigating small level changes between rooms or the edge of thick carpets. The X50s Ultra raises this capability to single 40 mm thresholds, which significantly expands navigation possibilities in homes with different levels or complicated transitions between spaces.
A notable difference is the incorporation of a proprietary voice assistant in the X50s Ultra, in addition to the Alexa and Google Home compatibility that both models share. This integrated assistant allows direct interaction with the robot without the need for external devices, facilitating quick commands during cleaning.
Multifunction Cleaning Base
Both bases offer auto-emptying of the dust container, washing and drying of mops with hot water and air respectively, as well as a detergent reservoir. The dust bag has a capacity of 3.2 litres in both cases, sufficient for several weeks without changes.
The self-cleaning of the washing tray evolves from second to third generation between the X40 Ultra and the X50s Ultra. This implies more thorough cleaning of the base's internal components, reducing the need for manual maintenance and preventing dirt accumulation.
The water tanks show slight variations. The X40 Ultra features 4.5 litres of clean water and 4 litres of dirty water, whilst the X50s Ultra slightly reduces these capacities to 4.2 and 3 litres respectively. This difference barely affects medium-sized homes in practice, although for very large surfaces the first model offers slightly more autonomy between refills.
Both models support a plumbing connection kit that is purchased separately, allowing complete automation of water filling and emptying. It doesn't come integrated as standard, but it's an interesting option for those seeking maximum autonomy.
Dimensions
The Dreame X50s Ultra stands out for its reduced height: 79.5 mm versus the X40 Ultra's 97 mm. This difference of almost two centimetres is decisive for accessing under low furniture, sofas or beds with little clearance from the floor. The diameter barely varies: 350 mm versus 352 mm.
The base dimensions also change. The X50s Ultra is wider (390 mm versus 340 mm) but less tall (499 mm versus 590.5 mm) and somewhat less deep (423 mm versus 456.7 mm). This can influence the base's location depending on the available space in each home.
Real-World Usage Experience
For homes with pets, the X50s Ultra's dual HyperStream brush makes a clear difference. The 35,000 Pa power combined with this anti-tangle system significantly reduces maintenance of the main brush, something that is especially appreciated during shedding seasons.
The more recent model's hot water mopping improves results on kitchen floors or areas where grease accumulates. For households with young children or where deep hygiene is prioritised, this function provides real value.
The X50s Ultra's ability to overcome 40 mm thresholds opens up possibilities in homes with complex layouts or small level changes that other robots cannot navigate. The X40 Ultra, with its 22 mm, covers usual needs but may encounter limitations in specific cases.
The X50s Ultra's reduced height is especially practical in homes with Scandinavian furniture or low beds, where every millimetre counts for accessing areas that would otherwise remain uncleaned.
Conclusion: Which to Choose?
Choose the Dreame X40 Ultra if you're looking for a high-end Dreame robot vacuum with more than sufficient performance for most homes, you prioritise a base with larger water tank capacity, and you don't need maximum suction power or hot water mopping. It's a solid option for homes of up to 200 square metres without long-haired pets or particularly thick carpets.
Choose the Dreame X50s Ultra if you need the maximum available suction power, you have pets that shed a lot of hair and value the dual anti-tangle brush system, you want hot water mopping for superior hygiene, you need to access under very low furniture thanks to its 79.5 mm height, or you're looking for the best ability to overcome obstacles of up to 40 mm. The integrated voice assistant and recognition of 280 obstacles make this model the most advanced option for those who prioritise the latest technology and maximum automation in home cleaning.
