01Navigation and mapping types
Random bounce navigation — the old approach — is inefficient and misses spots. LiDAR (laser) mapping creates accurate floor plans and enables systematic coverage; found on mid-to-high-end models. Camera-based mapping is cheaper but struggles in low light. For most homes, LiDAR mapping is worth paying for from $300+.
02Suction power and floors
Suction is measured in Pascals (Pa). For hard floors, 1500–2000Pa is ample. For thick carpet, look for 3000Pa+. Robot vacuums excel on hard floors and low-pile carpet; they struggle on high-pile or shag rugs and will avoid or get stuck on thick rug edges.
03Self-emptying bases: worth it?
Self-emptying bases collect debris from the robot into a larger bag, letting you ignore it for weeks rather than days. If you have pets or heavy debris, a self-emptying base pays for itself in convenience. Expect to pay $150–$300 more for the base. Bags need replacing every 30–60 days depending on use.
04Vacuum-mop combos
Combination vacuum-mop robots like the Roomba Combo j9+ vacuum and mop in a single pass. Quality varies significantly. The best models lift their mop pad automatically when crossing carpet. Cheaper combos simply drag a damp pad, which can leave carpets damp.