The Amazon page for this model shows it as currently unavailable. Details come from the older review and the maker’s claims. Replacement picks were checked on Amazon on October 15, 2026. CADR, noise and warranty figures come from the older review and were not retested.
The Okaysou AirMic4S was a small, quiet purifier with a long warranty. Its Amazon page is currently unavailable. This page keeps the review for owners and points to what to buy now.
Table of Contents
Best Replacement Today
Price on Amazon: $43.98 | 4.6 stars from 45,932 ratings (checked October 15, 2026)
What the AirMic4S Was
The AirMic4S was a compact purifier with an ABS plastic body, a 12-vane fan and a size of about 8.7 by 8.7 by 11.8 inches. The older review said it has a pre-filter, an H13 HEPA filter and an activated carbon filter, with a claimed 99.97 percent capture of particles. It came with a 5-year warranty. The Amazon page shows it as currently unavailable as of October 15, 2026, with no price.
Looking ahead, the Okaysou AirMic4S shows how quickly a small purifier can disappear. The Amazon page now shows it as currently unavailable, and only the filters are still listed, at $27.99. The catch is that owners are left with a machine whose filter supply may thin out.
What the Older Review Said
- Filters. Three stages. The H13 filter has 130 folds and is rated for 4,320 hours, about six months of nonstop use.
- Noise. About 24 dB in sleep mode, with three fan speeds.
- Sensor. A sensor reads the air and adjusts the fan.
- Filter light. Blinks when it is time to change, then a 3 second press resets it.
- Weak spot. Not very effective on smoke.
- Warranty. 5 years.
The phrase medical grade on the old page is marketing. No rule defines it for home purifiers. Judge the unit by its CADR and filter type.
The risk to watch is the coverage claim. The older review said the AirMic4S filters the air three times an hour in 288 square feet, or five times an hour in 140 square feet. With a CADR of 74 CFM, the math gives about two air changes an hour in 288 square feet, so the smaller room figure is the useful one. Expect more listings that call small units medical grade, a phrase with no standard behind it. Size by CADR and keep the room small.
CADR and Real Room Size
The older review gave a CADR of 125 cubic meters an hour, or 74 CFM. In a 140 square foot room with an 8 foot ceiling, that is 1,120 cubic feet, so one air change takes about 15 minutes, or four an hour. In a 288 square foot room, it holds 2,304 cubic feet, so one air change takes about 31 minutes, or about two an hour. Read what CADR means for the full method.
Filters Still Sold
An AirMic4S replacement filter is still listed on Amazon at $27.99. Check that it is the filter for the AirMic4S and not for another Okaysou model. The older review said to replace the filter about every 6 months. Use the air purifier filter replacement cost guide to plan the cost.
What to Buy Instead
The older review compared this unit with the Airthereal APH260. For a small room, the Levoit Core Mini-P has far more ratings. For more bedroom picks, read air purifiers for a bedroom. Other Okaysou models are covered in the Okaysou AirMax8L review, and a similar small unit in the Hathaspace HSP001 review.
Prices and Alternatives on Amazon
Prices and ratings were checked on Amazon on October 15, 2026.
Price on Amazon: $43.98 | 4.6 stars from 45,932 ratings (checked October 15, 2026)
The Levoit Core Mini-P is a small purifier for desks, dorm rooms and bedrooms. It has a 4.6 rating from over 45,000 ratings.
Price on Amazon: $89.99 | 4.7 stars from 109,039 ratings (checked October 15, 2026)
The Levoit Core 300-P is listed with a CADR of 143 for smoke, 153 for dust and 167 for pollen. It has a 4.7 rating from over 109,000 ratings.
Price on Amazon: $78.92 | 4.6 stars from 4,124 ratings (checked October 15, 2026)
The SilverOnyx is a five-filter small purifier reviewed on this site. It has a 4.6 rating from over 4,100 ratings.
Price on Amazon: $169.99 | 4.5 stars from 2,574 ratings (checked October 15, 2026)
The Blueair Blue Pure 311i Max is listed for up to 2,107 square feet with Wi-Fi, auto mode and 23 dB quiet filtration. It has a 4.5 rating from over 2,500 ratings.
Pros and Cons
Pros: compact and light; quiet, 24 dB in sleep mode; H13 HEPA and carbon filters; 5-year warranty; filter reset light.
Cons: currently unavailable on Amazon; weak on smoke; coverage claim is overstated for 288 square feet; medical grade is marketing; filter supply is thin.
FAQ
Is the Okaysou AirMic4S still sold on Amazon?
The Amazon page shows it as currently unavailable as of October 15, 2026, with no price. Only the filters are listed.
How big a room does it clean?
About 140 square feet at four to five air changes an hour. In 288 square feet, it gives about two changes an hour.
How loud is it?
About 24 dB in sleep mode, per the older review.
Is it really medical grade?
The phrase has no standard behind it for home air purifiers. Look at the CADR and the filter type.
Final Word
The AirMic4S was a decent little purifier, but it is out of stock. A Levoit Core Mini-P or Core 300-P gives you a published CADR and far more reviews.
What happens next: the AirMic4S may return, as other Okaysou models have. Until then, small units with a published CADR and a deep review count are the safer buy.
Related Guides
Keep going with Hathaspace HSP001 review, Okaysou AirMax8L review, air purifiers for a bedroom, what CADR means and air purifier filter replacement cost guide.
