Score 7.4 out of 10
Comparison · 2 models
Comparing 2 robot vacuums
Your shortlist side by side: today’s price, our score and every fact the maker states.
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- Best on the most facts
Blueair Blue Signature LargeOn the market since June 2025
No price today
not in our ranking Best on 1 fact -
- Highest score
Prices updated at 21:30
Side by side
Green is the best of these 2, also when they share the lead.
Drag a model by its header to move its column, or use the arrows.
| | | |
|---|---|---|
| Price and ranking | ||
| The lowest price today at a shop that delivers to you, delivery included. A price with an asterisk comes from a shop abroad, and its delivery cost is our own estimate. Lowest price | – | 284 €OTTO |
| Our own score out of 10: 60% measured facts and 40% shop ratings. Price does not count. Score | not in our ranking | |
| Where the model stands in our ranking, among the purifiers for the same size of room. Rank | – | rank 1 of 1 for open-plan spaces |
| The average of the stars buyers give at the shops, with the number of reviews behind it. We only compare it from 20 reviews. Customer rating | – | – |
| Room size | ||
| The size of room the purifier suits, with the largest room the maker names for it. Room size same on both | open-plan spacesup to 65 m² | open-plan spacesup to 135 m² |
| Size, noise and age | ||
| How tall the purifier is. It decides whether it fits on a shelf or under a window sill. In this comparisonWhen it matters
| 43.7 cm best | 52 cm |
| The month the model first went on sale. It shows how old the technology in it is. On the market since | June 2025 | February 2025 |
| Smart features and warranty | ||
| Whether you can control the purifier from a phone app, over wifi or only nearby over Bluetooth. App control same on both | Wi-Fi | Wi-Fi |
| Matter is the standard that lets devices from different makers work together. With it you can run the robot outside the maker’s own app. Matter same on both | no (assumed) | no (assumed) |
| Which voice assistants the robot works with, such as Google Assistant or Alexa. Voice assistants | – | Alexa, Google Assistant |
| Cleaning performance | ||
| How much clean air the purifier delivers an hour, measured with smoke, dust and pollen. A higher figure cleans a bigger room or the same room faster. In this comparisonWhen it matters
| 773 m³/h | 520 m³/h |
| The test the CADR comes from. AHAM AC-1 and the DOE test are independent and comparable. A maker's own test is not. CADR measured to | DOE test | GB/T 18801 (Chinese standard) |
| The CADR measured with tobacco smoke, the finest of the three test particles. It is the figure to read for wildfire smoke. CADR for smoke | 773 m³/h | – |
| The CADR measured with dust. CADR for dust | 737 m³/h | – |
| The CADR measured with pollen. CADR for pollen | 765 m³/h | – |
| The CADR measured for particles under 2.5 microns. CADR for fine particles (PM2.5) | 754 m³/h | – |
| The room size where the purifier changes the air 4.8 times an hour under a 2.5 m ceiling, worked out from its CADR. We use it so every model is compared on the same rule. In this comparisonWhen it matters
| 64 m² | 43 m² |
| The room size the maker states. Makers use different rules, so we show it but never rank on it. In this comparison | 65 m² | 135 m² |
| Filter | ||
| How fine the filter is. True HEPA and H13 catch at least 99.97% of particles at 0.3 microns. HEPA-type is a weaker claim with no test behind it. When it matters
| HEPA-type | Not stated |
| Whether the particle and carbon layers are one filter or separate ones. Separate filters let you replace only the part that is spent. Filter layout same on both | One combined filter | One combined filter |
| A filter of activated carbon that takes out smells and some gases. It does not catch particles. When it matters
| yes | yes |
| Replacement filter part number | – | FY3200 |
| Running costs | ||
| How long the maker says a filter lasts, in months of normal use. A filter that is spent cleans less. In this comparisonWhen it matters
| 12 months | 12 months |
| The electricity the purifier uses in a year, as its maker states it. Multiply it by your price per kWh for what it costs to run. When it matters
| 235 kWh | – |
| Noise and power | ||
| The sound level at the lowest speed, as the maker measures it. In this comparisonWhen it matters
| 23 dB | 15 dB |
| The sound level at the highest speed, as the maker measures it. In this comparisonWhen it matters
| 55 dB | 48 dB |
| The power the purifier draws at its highest speed. In this comparison | 42 W | 36 W |
| Air delivered for each watt, the ENERGY STAR measure. Higher is better. Energy efficiency (IEF) | 11.1 cfm/W | – |
| Certified by ENERGY STAR for the energy it uses to clean the air. ENERGY STAR certified | yes | – |
| Air quality sensing | ||
| The fan speed follows the air quality the sensor reads. When it matters
| yes | yes |
| What the purifier measures in the air. A particle sensor lets it speed up and slow down by itself. Air quality sensors | – | PM2.5 |
| Build | ||
| The purifier’s shape: a small tabletop unit, a tall tower, a box that stands on the floor or a unit mounted on the wall. Shape same on both | Floor box | Floor box |
| How wide the purifier is. With its depth it decides how much floor it takes up. In this comparison | 393.7 mm | 285 mm |
| How deep the purifier is, front to back. In this comparison | 393.7 mm | 285 mm |
| What the purifier weighs. It counts most if you move it from room to room. In this comparisonWhen it matters
| 6 kg | 6.2 kg |
| Extras | ||
| An ioniser charges particles so they settle. Some also make a little ozone, which is why a switch to turn it off matters. When it matters
| None | None |
| Certified by the California Air Resources Board as making little ozone. CARB certified | yes | – |
| The ozone the purifier gives off, in parts per billion. California allows at most 50. Ozone produced | 3 ppb | – |
| Warranty and certification | ||
| The CADR is verified by AHAM, the US trade body that runs the test. AHAM Verifide certified | yes | – |
| The warranty the maker gives in Germany. Consumer law here stands apart from it and can last longer. In this comparison | 1 year | 2 years |
| Maker model numbers | – | AC3220/10; AC3221/13 |
Facts as the maker states them. A dash means the maker does not name it. Each model’s page gives the source of every fact. Noise is the maker’s own figure, so we do not judge it, and a customer rating only counts from 20 reviews.
The score is out of 10: 60% measured facts and 40% shop ratings. A model is ranked only when its CADR is known. Method. Models whose CADR we do not hold yet, so they are not in our ranking. We do track their prices.
Score 7.0 out of 10
Score 4.8 out of 10
Not ranked
Not ranked
Not ranked
Not ranked
Lowest price at every shop that delivers to Germany, VAT and delivery included. * = delivery cost and VAT estimated for a foreign shop.
Robot vacuum market report, September 2026 A median price of – and 0 new models.
Frequently asked questions
What does a good air purifier cost in Germany?
The models in our ranking run from about 132 € to 386 € today. We show the lowest verified price of the day per model, VAT and delivery included.
How big an air purifier do I need?
Match it to the size of the room. Each model in the ranking is grouped by the room size its maker states, and the lists keep a model out when it states none. A common rule of thumb is a clean air delivery rate (CADR) in m³/h of at least 12 times the room’s floor area in m², for a ceiling of 2.4 metres.
What is the difference between HEPA H13 and True HEPA?
Both are high-efficiency filters. True HEPA is the American name for a filter that catches 99.97% of particles of 0.3 micrometres, and H13 is the European class for 99.95%. We read the class the maker states and do not treat a filter called HEPA-type or HEPA-like as either.
Can an air purifier make ozone?
Some can, mostly models with an ioniser or a plasma feature. California limits ozone from indoor air cleaners to 50 parts per billion, and the CARB certification shows a model meets that limit. Our asthma filter leaves out models whose ioniser cannot be switched off.
How often do you update the prices?
Every day, at every shop we follow. We read the prices from the shops’ own product feeds and web shops. We check them for errors and keep them, so every product page shows what a price did over the last 90 days. We only call a discount real when the price also sits below the level of the preceding 30 days. We link to Amazon too, but show no Amazon price until we read it through Amazon’s own API. Until then the price is on Amazon itself. Per shop: how and how often
Where we check prices
We read prices every day at most shops, from their product feed or web shop. We check them for errors and keep them, so you can see what a price did over the last 90 days. We link to Amazon too, but show no Amazon price until we read it through Amazon’s own API. Until then the price is on Amazon itself.
Whose tests we use
Beside each model we also show where these testers place it in their own lists, without counting it in the score:
How we combine measured facts and owners’ ratings into one score is on the method page.
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