Buying
How Much Suction Power Does a Robot Vacuum Need?
Suction power is the spec most brands lead with, measured in Pascals (Pa). More is not always meaningfully better once you cross a reasonable threshold.
What Pa actually measures
Pascals measure the vacuum’s pressure differential — roughly, how hard it pulls. It is a useful comparison point between models but is not directly comparable across brands that measure it differently, so treat it as a rough guide.
Hard floors vs carpet
Hard floors need relatively little suction to lift dust and crumbs. Carpet, especially medium-to-thick pile, needs meaningfully more to pull debris up out of the fibers, which is why many robots automatically boost power when they detect carpet.
The practical range
For a mixed home with light carpet, mid-range suction paired with good brush design usually outperforms a higher Pa number with a weak brushroll. For heavy pet hair or thick carpet, prioritize both suction and a tangle-resistant brush design together.