Vacuum specs 101

Suction is the most quoted and least standardized number in the industry. Robot brands quote pascals (Pa) — static pressure at the inlet with no airflow. Dyson quotes air watts (AW) — a measure that combines pressure with airflow. Other brands quote motor watts, which measures electricity consumed, not dirt moved. None of these are measured under a common test standard, and none of them capture the thing that cleans your carpet: the brushroll and how well the head seals against the floor.

The honest way to use suction figures: compare within one brand and one unit, treat cross-brand gaps under ~30% as noise, and ignore the number entirely for brands that don’t publish one — iRobot and Shark never quote Pa, and their machines clean fine. 86 of our 267 models list “Not disclosed” for exactly this reason.

In this catalog, robot Pa claims run from 2,000 Pa to 42,000 Pa on the Mova V70 Ultra Complete (median 18,000 Pa), while the strongest air-watt figure is 400 AW on the Samsung Bespoke AI Jet Ultra. Those two numbers are not comparable — and any site that ranks them together is making it up.

Navigation decides whether a robot cleans your whole floor or wanders until the battery dies. LiDAR spins a laser to map rooms in the dark, produces accurate floor plans, and enables no-go zones in the app — it’s the technology behind 94 of the 104 robots we track. Camera-based systems (alone or paired with LiDAR) add obstacle recognition — cords, socks, pet accidents — at the cost of putting a networked camera on your floor and struggling in dark rooms. Gyroscope models track their own movement in straight-line passes: far better than the old random-bounce bots, but they still miss spots and can’t save maps.

The practical hierarchy for most homes: LiDAR for mapping accuracy, add a camera only if floor clutter is your reality, and accept gyroscope only at bargain prices in small spaces. Privacy-conscious buyers should filter for LiDAR-only — we keep a camera-free list for exactly that.

A self-empty station sucks the robot’s small onboard bin into a sealed bag at the base after each run, stretching bin duty from every-run to every-month. It’s the robot feature owners most consistently say they’d buy again — 100 models here have one — and it matters more in practice than an extra thousand pascals.

The costs are honest but real: docks are the size of a small trash can, replacement bags run $15-30 a year (a few models use bagless compactor bins instead), and the empty cycle is a ten-second jet-engine burst — schedule it for daytime. On mop combos the dock escalates further: pad washing, hot-air drying, clean and dirty water tanks, even detergent dosing. Each level of automation is one less chore and one more thing to descale quarterly.

120 of our 267 machines mop, and the quality range is enormous. The generations, worst to best: a dragged damp pad (moistens dust, calls it mopping), vibrating/oscillating pads (actual scrubbing pressure), spinning discs that extend to reach edges, and rollers that wet, scrub, and squeegee in one rotation. Dock automation decides whether you’ll actually use it: pads that wash and hot-dry themselves get used daily; pads you must unclip and rinse get used twice, ever.

Water-tank specs mislead on dock-fed flagships — the robot itself carries a small onboard tank the dock refills mid-run, so compare dock tank sizes, not the robot’s. And on carpet, what matters is mop lifting: the good combos raise the pad 10-20 mm or leave the mop at the dock entirely; the bad ones drag a damp pad across your rug. Dedicated hard floor washers skip the compromise — bigger tanks, real scrubbing pressure, self-cleaning rollers — at the cost of you pushing them.

Every runtime figure you’ll ever see was measured in the machine’s gentlest mode — Eco, brushroll off, on hard floor. Turn on max power on carpet and a “60-minute” stick delivers 8-15 minutes; a “180-minute” robot drops to under an hour. That’s not lying so much as an industry-wide agreement to measure the flattering case, and it’s why we print the manufacturer’s max figure and tell you to divide by three for boost-mode reality.

Catalog range: 10 minutes on the Shark WANDVAC Cordless Handheld Vacuum up to 350 minutes on the Ecovacs Deebot T90 Pro Omni (median 90 min). Two things matter more than the headline: robots recharge themselves and resume, so their number barely matters in a home under ~2,000 sq ft — and stick batteries are consumables that fade within a few years, so whether the pack is swappable (and what a replacement costs) is the spec with teeth. 69 machines here are corded and opt out of the whole question.

Decibels are logarithmic: 10 dB more reads as roughly twice as loud. The gap between our quietest machine — the SwitchBot K10+ at 48 dB — and the loudest (87 dB on the Milwaukee M18 FUEL PACKOUT 2.5 Gallon Wet/Dry Vacuum) is the difference between a normal conversation and a running shower. Under ~60 dB you can take a call in the next room; over ~70 dB the vacuum owns the house while it runs.

Caveats: manufacturers measure in their quietest mode (see the runtime section for this pattern), self-empty docks hit 80+ dB for their ten-second cycle regardless of how quiet the robot is, and pitch matters as much as level — brushroll clatter on hard floor annoys at numbers that look fine on paper.

Bin sizes tell you how often you’ll be emptying. Robot onboard bins run 300-500 ml — a day or two of a shedding dog — which is the entire argument for a self-empty dock’s 2.5-3 L sealed bag. Stick bins run 0.5-1 L and fill fast in max mode; upright and canister bins/bags run 1-6 L and can go a month.

The number understates real life on two fronts: fine dust cakes the bin walls and filters long before the bin looks full, and pet hair fluffs to fill a bin at a fraction of its rated volume. If capacity is why you’re shopping, a bagged machine or a self-empty dock beats chasing a bigger bin.

A true HEPA filter captures 99.97% of particles at 0.3 microns — the size that stays airborne and reaches deep into lungs. The trap in vacuum marketing is the filter without the seal: if air can escape around the filter through case seams, the machine exhausts allergens at nose height no matter what the filter media captures. The magic words on a spec sheet are “sealed system” or “whole-machine filtration”, not the HEPA badge alone.

103 of our 267 machines claim HEPA-grade filtration. For allergy and asthma households it’s the spec that should override everything else — and it pairs naturally with bagged designs, which add dust-free disposal. Everyone else can live happily with washable standard filters; just actually wash them, because a clogged filter is the number-one cause of “my vacuum lost suction”.

Bagless won the market on running costs and the weird satisfaction of seeing the dirt; bagged quietly kept winning on everything allergy-related. A bag is itself a filter stage, it maintains suction more evenly as it fills, and disposal is sealed — no dust cloud over the trash can, which is exactly the moment bagless machines re-aerosolize what they captured.

The economics: bags cost $15-25 a few times a year, forever. Bagless costs nothing ongoing but demands filter washing and a dusty emptying ritual. The 30 bagged machines in this catalog — mostly canisters and uprights — are the default pick for allergy households, and the premium ones (Miele, Sebo) treat the bag as a core part of a sealed system rated to run a decade.

198 of our machines are cordless (counting robots, which have no choice), 69 are corded. The tradeoff is simple and permanent: cordless buys you the freedom that makes you actually vacuum more often; corded buys unlimited runtime, consistent power that never sags as a battery drains, and a machine that works identically in year six.

The pattern that works in real homes: corded for the weekly deep clean if you have serious carpet, cordless for the daily grabs. If you’re buying exactly one machine, match it to your floors — and remember the battery section above: a cordless machine’s real lifespan is its battery’s.

Weight decides whether a stick vacuum gets used or parked. Under ~6 lbs one-hands comfortably up stairs and along ceilings; over ~10 lbs is two-hands territory and how uprights earn their “workout” reputation. Our catalog spans 1.4 lbs on the Shark WANDVAC Cordless Handheld Vacuum to 26.9 lbs on the Shark PowerDetect ThermaCharged NeverTouch Pro.

For robots, the dimension that matters is height: a 3.9 in robot clears most sofas and beds, a 4.5 in one doesn’t, and that gap decides whether the dustiest zones in the house get cleaned at all. Some 2025-generation flagships drop retractable LiDAR turrets specifically to duck lower. Check your furniture clearance with a tape measure before you check reviews.

Warranty length is the closest thing to a manufacturer telling you how long they expect the machine to last. Robots and sticks cluster at 1-2 years — battery and electronics limited. Premium canisters and uprights run 5-10 years (Miele, Sebo, Riccar), backed by actual repair networks and available parts, which is why a $700 canister can be cheaper per year than a $300 stick replaced twice.

Read the fine print on cordless machines: the battery often carries a shorter warranty than the vacuum around it, and it’s the part that fails first. A brand that sells replacement batteries at a sane price is quietly promising the machine a second life.