Buying guide

Match the robot to the pool, then to your patience

A robotic pool cleaner is a small vehicle with a pump. It is not a magic fish. The right one is the machine whose coverage, power source, and filter match the bowl you already have.

1. Measure before you read a star rating

Sketch the water surface. Length times width is close enough for a rectangle. For a freeform pool, break it into rectangles and add them. Write down the deepest point and whether the main drain sticks up. Those three facts eliminate more bad purchases than any review score.

Coverage claims on this site are copied from the listings we checked, and some brands disagree with themselves. The Dolphin title and older Dolphin copy do not use the same length. DEENO's Hydro 4 page cites more than one area. If you are close to the ceiling, believe the smaller number.

2. Corded or cordless is a lifestyle choice

A corded robot such as the Dolphin Nautilus CC Plus or the DEENO Hydro 4 runs until the cycle you chose is over. You manage a floating cable, a GFCI outlet, and a lift at the end. You do not manage a battery that fades in year three.

A cordless robot such as the OYEMIA SAT25, the WYBOT B1, the Aiper Seagull Pro, or the Beatbot AquaSense 2 has no cable to wrap a ladder. It has a hard stop when the pack is done. Buy the runtime that finishes your pool with time left over.

3. Read the waterline line twice

"Climbs walls" is not "scrubs the waterline." The SAT25, the AquaSense 2, the Seagull Pro, and both DEENO machines list the waterline. The Nautilus CC Plus climbs and, on Dolphin's own chart, is not the waterline scrubber. The WYBOT B1 listing we checked leads with floor and walls. If the tile ring is the complaint, buy a robot that names it, and keep a brush anyway.

4. Microns tell you what comes back out

The SAT25 publishes a 300 micron basket. The DEENO machines publish 180 micron in a 4.1 liter tray. Finer mesh holds the dust that makes water look tired. It also needs a rinse every cycle. A robot that leaves a dirt trail is often a packed filter, which is why that guide exists once it publishes.

5. Warranty and review count are different evidence

The SAT25 is the featured cordless pick because the listing fits a common inground pool. Its public review trail was thin on the day we checked, and the warranty is one year. The Dolphin has thousands of ratings. The Beatbot has hundreds and a three-year replacement claim. A long warranty does not shrink your pool. A short review history means you use the return window on purpose.

6. Geometry the brochure will not fix

• A raised drain cover parks tracks and wheels. See the drain guide when it is live.
• Sharp stair noses and sun shelves strand small robots.
• Wrinkled vinyl liners grab treads.
• A greasy waterline is chemistry and a brush, then a robot.

The 2026 shortlist puts the SAT25 first and keeps the corded DEENO machines available without pretending they are the default. Head-to-head pages cover SAT25 versus WYBOT B1, SAT25 versus Seagull Pro, and Beatbot versus Dolphin.

Questions