A robot vacuum cleans your floors every day while you are at work – and once you have one, it is hard to go back. But the spec sheets are full of numbers. Here is what actually matters.

1. Suction power (Pa)

Suction is measured in pascals (Pa). As a guide:

  • 2,000–3,000 Pa – hard floors and low-pile rugs, light daily cleaning.
  • 4,000–6,000 Pa – mixed floors, carpets and pet hair.
  • 8,000 Pa+ – thick carpets, big homes and heavy shedders.

Higher suction uses more battery, so most robots let you choose a quiet, standard or max mode per room.

2. Navigation and mapping

LiDAR (the round laser turret on top, sometimes called TrueMapping) builds an accurate map of your home, cleans in neat lines and works in the dark. You can set no-go zones and clean single rooms from the app. Cheaper robots with gyroscope or random navigation are fine for one open room but miss spots in bigger homes.

3. Vacuum only, or vacuum and mop?

A 2-in-1 robot drags a wet mop pad behind the brush – great for kitchen tiles and wooden floors to pick up dust and light marks. Better models lift the mop on carpets or let you set carpet no-mop zones. If your home is mostly carpet, a vacuum-only robot is simpler.

4. Auto-empty station

An auto-empty base sucks the dust out of the robot into a sealed bag that lasts weeks. Ideal for allergy sufferers and pet owners – you barely touch the robot.

5. Battery and runtime

Look for 150+ minutes for a typical 3-bed house. Most robots return to charge and then resume where they stopped.

6. Pets, hair and cables

  • Anti-tangle brushes stop long hair wrapping round the roller.
  • Obstacle avoidance (cameras or 3D sensors) helps the robot avoid socks, cables and pet accidents.
  • Tidy loose cables before the first run and use the app's no-go zones under desks.

Should you buy an open-box robot vacuum?

Robot vacuums are among the most returned items online – often because the buyer's home had too many stairs or rugs. That means you can get a premium ECOVACS model for a fraction of the price. We test every robot before listing it and list anything missing in red at the top of the description. Read what our condition grades mean.

See all vacuum cleaners →

Frequently asked questions

How much suction does a robot vacuum need?

For hard floors 2,000–3,000 Pa is enough. For carpets and pet hair, choose 4,000 Pa or more.

Are robot vacuums worth it?

Yes for most homes: daily automatic cleaning keeps dust and pet hair down, so you only need a full manual clean occasionally.

Do robot vacuums work on carpet?

Yes. Models with higher suction and carpet boost mode clean low and medium-pile carpets well. Very thick shaggy rugs are best set as no-go zones.

Can a robot vacuum go up stairs?

No. Cliff sensors stop them falling down stairs, but you need to carry the robot between floors. LiDAR models can store maps for several floors.

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