Quick verdict
The 539S is the better-performing pick in the $100 small-room class: more CADR than the Levoit Core 300S, a real PM2.5 number and an Energy Star rating. Buy it for a bedroom or office up to about 245 sq ft; if you value years of owner feedback and a mature app over the extra airflow, the Core 300S is still the safer choice.
Ideal for
- Bedrooms and home offices up to ~245 sq ft (e.g. a 14x17 room)
- Budget buyers who want Wi-Fi, Alexa and a numeric PM2.5 readout
- Shoppers comparing the Levoit Core 300S who want more airflow for similar money
Not ideal for
- Living rooms over ~250 sq ft (the Winix 5530 has 60% more CADR)
- Heavy odor or smoke households (one thin 3-in-1 carbon layer)
- Anyone who wants Turbo on a physical button (it is app-only)
The full picture
The Dreo Air Purifier 539S (model DR-HAP009S) is the Wi-Fi version of Dreo's 539. It carries an AHAM Verifide 158 CFM CADR, a 3-in-1 filter (pre-filter, HEPA, activated carbon), a PM2.5 sensor with a numeric display, Alexa support and Energy Star certification. RTINGS found it cleaned its test room about 20% faster than the Levoit Core 300S on top speed. The trade-offs are a $29.99 filter Dreo rates for 6–8 months, Turbo mode that is only reachable from the app, and a short track record.
Dreo 539S at a glance
- CADR — smoke (CFM)
- 158
- Coverage (sq ft)
- 245
- Coverage detail
- 4.8 ACH (245 sq ft); Dreo's 1,176 sq ft claim is 1 ACH
- Filtration
- 3-in-1 cylinder filter: pre-filter + HEPA + activated carbon
- HEPA filter
- HEPA (Dreo states 99.97% at 0.3 µm; grade not published)
- Filter life (months)
- 7
- Filter cost
- ~$50/yr ($29.99 filter every 6–8 months)
- Noise — low (dBA)
- 18
- Auto mode
- Yes
- Air quality sensor
- Yes
- Smart app / Wi-Fi
- Yes
- Room size
- Small-Medium
- Ozone-free
- Yes
- Energy Star
- Yes
- Notable feature
- Numeric PM2.5 display; Energy Star rated at about 162 kWh/yr
Source: CADR, Energy Star figure, certifications, noise and the 12-month warranty from Dreo's 539S store page and Amazon listings (DR-HAP009S); filter price and interval from Dreo's 539/539S filter page; performance comparison and control notes from RTINGS's 539S review and Core 300S comparison (checked 2026-10-01). Research-based; not hands-on tested.
This is a research-based review — our analysis draws on manufacturer specifications, manuals, warranty terms, and verified owner feedback rather than our own hands-on testing, and we note where a detail couldn't be confirmed. How we review
The in-depth review
The Dreo 539S is one of the better ways to spend about $100 on a bedroom purifier. Its AHAM Verifide CADR of 158 CFM beats the Levoit Core 300S, it shows a real PM2.5 number, and it adds Wi-Fi, Alexa and an Energy Star rating. It suits rooms up to about 245 square feet. The catches are a $29.99 filter on a 6 to 8 month cycle, a Turbo mode that lives only in the app, and a short ownership track record.
Which 539 is this?
Dreo sells three purifiers with "539" in the name, and the filters are not all interchangeable. The 539S (model DR-HAP009S) is the Wi-Fi version. The plain 539 (DR-HAP009) has the same filter and touch controls but no app. The 539AS (DR-HAP009AS) is a pet edition with a replaceable pet-hair pre-filter, a pet lock and a chew-resistant cord. It takes a different, pricier HEPA Pro filter. This review covers the 539S. If you see "Macro" in a Dreo listing title, that is an older, separate product line.
How much room does it really clean?
At 158 CFM, the 539S delivers 4.8 air changes an hour in about 245 square feet, roughly a 14x17 bedroom. In a 12x12 room it manages about 8 changes an hour on its top setting. That gives it enough headroom to run on a quieter speed most of the night and still keep pollen and dust down.
Dreo's box says 1,176 square feet. That figure works out to one air change per hour, which is a slow background refresh rather than the pace you want for allergies or smoke. In a 400-square-foot living room, the 539S would manage under 3 changes an hour even flat out. Our room size calculator shows where your room falls.
The useful independent check comes from RTINGS. In its side-by-side with the Levoit Core 300S, the 539S cleaned the test room about 20% faster on max. The gap narrowed but did not close at quieter speeds. On paper the difference is 158 vs 141 CFM, and the lab result lines up with that.
Filters and the three-year bill
The 539S uses one cylindrical 3-in-1 cartridge: a pre-filter, a HEPA layer that Dreo rates at 99.97% of 0.3-micron particles, and an activated-carbon layer. Dreo sells the genuine Dreo 539S Replacement Filter for $29.99 in white or black to match the unit, and rates it for 6 to 8 months. The carbon is a thin layer, so it will take the edge off cooking smells but will not handle a smoker's room for long.
Three-year math, assuming the unit runs daily:
- Purchase: about $80 on sale, $110 at list
- Filters: 4 to 5 replacements (the first filter is in the box), $120 to $150
- Electricity: Dreo's listing gives an Energy Star figure of about 162 kWh a year, or about $28 at $0.17/kWh. That is $83 over three years. Dreo does not publish per-speed wattage, and Energy Star's figure assumes a set daily runtime, so leaving it on Turbo around the clock would cost more.
That comes to roughly $280 to $340 over three years. Filters are the biggest line after year one. For comparison, the Winix 5530 costs around $480 to $540 over the same period on a worst-case power estimate, but it has 60% more CADR. The filter cost calculator lets you rerun the numbers with your local prices.
Noise and night use
Dreo quotes 18 dB in Sleep mode. It does not publish a figure for the top speed, and the independent measurements available so far do not give a full per-speed breakdown. RTINGS does note that the 539S is louder than its smaller sibling, the Dreo 338S, which is the expected trade for more airflow.
One bedroom detail to know before you buy: RTINGS found the display can be dimmed but not switched fully off. The Levoit Core 300S can go fully dark. If any glow keeps you awake, that one difference may matter more than the CADR.
The smart features: what earns its keep
The PM2.5 readout is the standout. A number on the front tells you when cooking or a candle has spiked the room, and it makes Auto mode easier to trust. The Dreo app adds remote control and Alexa voice commands, plus a 24-hour timer.
The odd decision is Turbo. RTINGS reports that both the 539S and the 338S expose Turbo only in the app, not on the unit's own buttons. If you share the room with someone who does not use the app, the top speed is effectively hidden from them. Auto mode will still ramp the fan up when the sensor sees a spike.
What to watch for
The 539S is new, and there are not yet enough owner reviews to judge how its fan and sensor hold up over two or three years. Dreo's US store lists a 1-year limited warranty on new units, half the two years Levoit and Winix give their purifiers. Levoit and Winix both have longer records in this size class. Dreo also publishes a thinner spec sheet than they do: no dust or pollen CADR split, no wattage, and no top-speed noise.
Is it the right one for you?
Buy the Dreo 539S if your room is 120 to 245 square feet and you want the most verified airflow and a live PM2.5 number for around $100. It is a stronger buy than the Dreo 338S, which costs only about $10 less at list but has 37% less CADR.
Choose the Levoit Core 300S instead if you want a fully dark display, a long owner track record and a cheap, widely sold filter. You give up a little airflow. If your room is a living room or anything over 250 square feet, skip both and look at the Winix 5530. For more small-room options, see our best air purifiers for bedrooms.
Performance breakdown
Research-based editorial judgments from specs, warranty terms, and verified owner feedback — not lab measurements. How we score
Pros and cons
What works
- AHAM Verifide 158 CFM CADR, about 12% more than the Levoit Core 300S on paper
- RTINGS measured it clearing its test room roughly 20% faster than the Core 300S on max
- Numeric PM2.5 readout, Auto mode, Wi-Fi app and Alexa at a sub-$110 list price
- Energy Star rated at about 162 kWh a year, roughly $28 at $0.17/kWh
- No ionizer; CARB certified
What doesn't
- $29.99 filter on a 6–8 month cycle works out to about $50 a year
- Turbo mode is app-only, per RTINGS
- Display can be dimmed but not switched fully off (RTINGS)
- New model with few owner reviews so far; Dreo does not publish per-speed watts or a top-speed noise figure
More on the Dreo 539S
Best alternatives to Dreo 539S
Levoit
Levoit Core 300S
Best budget
A compact, quiet, smart True HEPA purifier for small rooms at a price that makes a second unit easy.
- 141 CFM CADR
- 219 sq ft
- $90–$110
Winix
Winix 5500-2
Best budget for larger rooms
More coverage than the usual budget pick, with a washable carbon filter that keeps running costs low.
- 232 CFM CADR
- 360 sq ft
- $150–$170
Levoit
Levoit Core 400S-P
Best round Levoit for mid-size rooms
The current Core 400S: a 231 CFM AHAM-verified smart cylinder for rooms up to about 358 sq ft, with a laser PM2.5 sensor.
- 231 CFM CADR
- 358 sq ft
- $160–$220
Shark
Shark NeverChange Air Purifier MAX
Best for skipping yearly filter changes
Shark's HP302 trades yearly filter buys for one long-life filter. Energy Star lists 204 CFM smoke CADR, so size it for ~316 sq ft, not 1,400.
- 204 CFM CADR
- 316 sq ft
- $240–$400 ($399.99 list; often $280–$300 on sale)
Frequently asked questions
What is the difference between the Dreo 539, 539S and 539AS?
The 539 (DR-HAP009) is the non-Wi-Fi model. The 539S (DR-HAP009S) adds Wi-Fi, the Dreo app and Alexa control, and uses the same filter as the 539. The 539AS (DR-HAP009AS) is a pet version with a replaceable pet-hair pre-filter, a pet lock and anti-tip and chew-resistant cord features, and it takes a different HEPA Pro filter.
How big a room can the Dreo 539S clean?
About 245 sq ft at 4.8 air changes per hour, based on its 158 CFM CADR. Dreo's 1,176 sq ft figure assumes one air change per hour, which is too slow for allergy season or smoke.
What filter does the Dreo 539S use?
The Dreo Air Purifier 3-in-1 HEPA Filter for 539/539S, sold in white and black to match the unit, at $29.99 on Dreo's store. Dreo rates it for 6–8 months. It does not fit the 539AS or 530S, which take the HEPA Pro filter.
Is the Dreo 539S better than the Levoit Core 300S?
On airflow, yes: 158 vs 141 CFM on paper, and RTINGS measured the 539S about 20% faster on top speed. The Core 300S has years of owner feedback and lets you switch the display fully off, which the Dreo cannot.
Does the Dreo 539S have an ionizer?
Dreo lists no ionizer or UV stage for the 539S; cleaning comes from its 3-in-1 pre-filter, HEPA and carbon cartridge. It is also CARB certified.