PuroAir 400 Review: 2,000 sq ft and No Published CADR

The PuroAir 400 is the largest purifier PuroAir sells, and the whole case for it fits in one number: the brand rates it to 2,000 sq ft per hour, double the 1,000 sq ft rating on the best-selling 240 and more than three times the 600 sq ft of the 130i. If the space you want to clean is an open-plan main floor rather than a bedroom, that coverage is the reason the 400 exists. It costs $324.99 standalone, or $279.99 if you attach an active filter subscription at checkout, both verified 2026-08-17 from PuroAir's own store feed.

Here is the direct answer. Buy the 400 if one machine has to cover a genuinely large room and price matters more to you than independently measured performance. Do not buy it expecting the paperwork that Coway, Blueair or IQAir provide: PuroAir publishes no clean air delivery rate and no HEPA grade for this unit, and independent testers including HouseFresh have argued the brand's real-world clearance trails the measured leaders. And if the room is 1,000 sq ft or under, the PuroAir 240 at $199.99 does the same job for $125 less. This review covers what PuroAir publishes for the 400, what it leaves out, what the subscription discount actually asks of you, and where the cheaper units are the better buy.

Quick answer

• Open-plan floor or large family room: the PuroAir 400 at $324.99 standalone or $279.99 with a filter subscription, the only unit in the line rated past 1,000 sq ft.
• Bedroom, office or medium room on a budget: the PuroAir 240 at $199.99, the same three-stage filter stack and auto mode for $125 less.
• Bedroom where noise decides it: the PuroAir 130i Smart at $124.99 standalone or $119.99 with a subscription, 27 dB on low and the only PuroAir with Wi-Fi and an app.

PuroAir·Clean Air & Water

PuroAir 400

The 400 is the one to buy if the room is actually big. PuroAir rates it to 2,000 sq ft against the 240's 1,000, and it is the only unit in the line built for an open-plan floor.

PRICE

$279.99 to $977

TIER

mid

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The PuroAir line at a glance

Every coverage figure is PuroAir's own rating and every price comes from the brand's store feed on the date shown. None of the three has a published CADR in our verified data. On filter grade, our catalog entry for the 240 records a true HEPA-14 filter, while the 400 and 130i product pages say HEPA and stop there.

What PuroAir publishes for the 400

Start with what is on the record. The 400 runs a three-stage stack: a pre-screen for hair and large debris, a HEPA layer for particulate, and activated carbon for odors and VOCs. PuroAir says it filters PM1, PM2.5 and PM10 down to 0.1 micron. An air-quality sensor drives an auto mode that steps the fan up on its own, and a front-panel light tells you when the filter is due. There is no Wi-Fi, app or voice control; those are exclusive to the 130i, and the 240 and 400 are manual units with indicator lights.

The living-with-it numbers are 31 dB at the lowest fan speed, 80W, and 14.7 lb in a tower that measures 14.4 by 8.1 by 21.5 inches. The 2,000 sq ft per hour rating is the headline. PuroAir backs the machine with a two-year warranty, extended to lifetime for as long as a filter subscription stays active.

That is a reasonable spec sheet for $324.99. What it is not is a performance sheet, and the gap between the two is the whole review.

What it does not publish, and why that matters

Two numbers are missing. The first is CADR, the clean air delivery rate, the industry figure for how much filtered air a purifier actually moves and the one that lets you compare purifiers from different brands and price tiers on the same scale. PuroAir does not publish one for the 400. The second is a HEPA grade. The product page says HEPA; it does not say H13 or H14, and we are not going to infer a grade the brand has not stated.

This matters because a room-size rating without a CADR behind it is a ceiling, not a measurement. We report 2,000 sq ft per hour as the brand's claim. What we cannot tell you is how many air changes per hour that represents in a real room, or how the unit's clearance compares to the purifiers in our best air purifiers guide that do publish the figure.

The independent record fills in some of the picture, and not in PuroAir's favor. Testing houses including HouseFresh have argued that PuroAir's real-world clean-air delivery trails the measured leaders once room size and run time are accounted for. That is a brand-level finding, and it cuts the same way for the 240 and the 130i. The practical response: treat 2,000 sq ft as a best-case number, size up rather than down, and run a higher fan speed than auto mode picks in a genuinely large space.

The price has two doors

PuroAir sells the 400 two ways, and the cheaper one comes with a string. Standalone, a single unit is $324.99 against a $349.99 compare-at price, verified 2026-08-17 from the getpuroair.com product feed. Bundle it with an active filter subscription and the price drops to $279.99, a $45 cut. The same subscription turns the two-year warranty into a lifetime one, so it is doing real work on both the price and the coverage.

Whether the $45 is worth it depends on the filter cost, and that is a number we cannot give you: the replacement filter price and interval for the 400 are not in our verified data. Our catalog records the 240's filters at about $40 every 6 to 8 months, but the 400 is a larger machine and we will not assume its cartridge costs the same. Find the per-filter charge and the shipping cadence on the checkout page and do the multiplication yourself before taking the subscription price. A subscription that runs for years can outspend a $45 discount many times over.

Multi-packs are the other door. The store feed lists a 2-pack at $505 and a 4-pack at $977, which works out to $252.50 and $244.25 per unit, under the $279.99 subscription price with no subscription attached. The $977 figure is the top of our catalog's price range for the 400, and it is four machines, not one. The 2-pack is the interesting one for anyone already planning a unit on each floor.

Living with it: noise, power and size

At 31 dB on its lowest fan speed the 400 is quiet enough for a living space, but it sits 4 dB above the 130i's 27 dB, the trade for the extra airflow; the 240 has no published dB figure in our data, so the 130i is the only comparison we can make. Fan noise at higher speeds is not in our verified data, and higher speeds are exactly what we are telling you to use in a large room, so plan on hearing it when it works hardest.

The 80W draw is more than four times the 130i's 18W, and again the 240 has no wattage in our verified data to set against it. Run flat out around the clock, 80W is roughly 58 kWh a month; auto mode will pull less as the fan steps down, but the ceiling is worth knowing if the plan is continuous operation. At 14.7 lb and 21.5 inches tall it is furniture rather than a device you carry between rooms, fine for a unit that lives on the main floor and wrong for anyone who wanted to move it into the bedroom at night.

Where it gives ground

It gives ground on evidence. No published CADR, no stated HEPA grade, and an independent testing record that questions the brand's coverage marketing. If a published performance number is a requirement, the 400 is out, and Coway Airmega, Blueair and IQAir are the brands that meet it.

It gives ground on price transparency. The headline $279.99 requires a subscription whose filter cost we cannot verify, and the honest standalone price is $324.99.

It gives ground on connectivity. No app, no voice control, no scheduling from a phone. The 130i has all three at less than half the price.

And it gives ground in any room under about 1,000 sq ft, where it is paying for coverage the walls will not let you use, at a price $125 above the unit rated for exactly that room. That is the case for the 240, so here it is.

When the 240 is enough

PuroAir·Clean Air & Water

PuroAir 240

The PuroAir 240 is the high-volume best-seller of the affordable air-purifier world: HEPA-14 plus activated carbon, a rating up to 1,000 sq ft, an auto air-quality sensor, and a price that undercuts the premium names. It is the no-fuss bedroom-and-office pick.

PRICE

$199.99 to $499

TIER

mid

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The PuroAir 240 is the volume best-seller of the line, rated up to 1,000 sq ft, with an activated-carbon layer and the same auto air-quality sensor and auto mode as the 400. On filter grade it carries the stronger statement: our catalog entry records a true HEPA-14 filter, more than PuroAir states for the 400. The price is $199.99, verified 2026-08-14, frequently discounted to roughly $159 per our catalog. Replacement filters run about $40 every 6 to 8 months. A 2-pack is $319 and a 4-pack is $499.

The 240 is enough when the room is a bedroom, a home office, or a medium living room. At 1,000 sq ft rated it covers most single rooms in most homes with margin, and it does so for $125 less than a standalone 400 and $80 less than the subscription price. That gap is not small. It is most of the cost of a second 240.

That second unit is the comparison PuroAir does not put on the page. A 2-pack of 240s at $319 is $5.99 cheaper than one standalone 400 at $324.99, and it puts two sensors and two 1,000 sq ft ratings in two rooms instead of one 2,000 sq ft rating in one spot. For a bedroom plus an office, two 240s are the better answer. For a single open-plan floor with no walls to split, one 400 keeps the coverage where the air is, and that is the layout where the larger unit clearly wins.

Where the 240 gives ground: the same independent testing caveat applies, and the 1,000 sq ft rating is a best case. Our catalog records a 1-year warranty for the 240 against 2 years for the 400, so confirm the current term at checkout. And the 400's 31 dB, 80W and 14.7 lb figures have no published equivalents in our 240 data, so the noise and size comparison stays qualitative: the catalog calls the 240 quiet on low and auto, and leaves it there.

When the 130i is the honest answer

If the room is a bedroom, the PuroAir 130i Smart is the unit to look at before either of the others. It is rated to 600 sq ft per hour, runs at a published 27 dB on its lowest setting, draws 18W, and weighs 4.39 lb in a roughly 8 by 8 by 13 inch box. It is the only PuroAir with Wi-Fi, an app, and voice control through Alexa or Google Assistant, and it costs $124.99 standalone or $119.99 with a filter subscription, verified 2026-08-17, with multi-packs at $209.99 for two and $399.99 for four. The same two-year warranty extends to lifetime while a subscription is active.

Where the 130i gives ground: 600 sq ft is a bedroom, a nursery or a home office, not a floor, and pushing it into an open living space is the mistake to avoid. The brand-level testing caveat applies here too, and no CADR or HEPA grade is published for it either. It is the right purchase for a sleeper who needs the machine to disappear, and the wrong one for anyone whose room is the reason they were reading about the 400.

Where it fits in a clean-air setup

A purifier only handles airborne particles and odors. If the home also has a damp basement, the purifier is working downstream of the problem, and our home air and water quality setup walks through the four jobs worth covering, humidity and drinking water included. Every PuroAir unit is a plug-in floor device with no install, which puts it alongside the gear in our no-install longevity setup for renters. The rest of PuroAir's lineup, with catalog prices, is on the PuroAir brand page.

Verdicts by buyer type

• One open-plan floor, one machine: the PuroAir 400 at $324.99 standalone, the only unit in the line rated past 1,000 sq ft. Take the $279.99 subscription price only after pricing the filters.
• Two rooms on two floors: the 2-pack of 240s at $319 beats one 400 at $324.99 on both price and placement.
• A large house, more than two rooms: the 400 2-pack at $505 or 4-pack at $977 brings the per-unit price to $252.50 and $244.25 with no subscription attached.
• A bedroom or office under 1,000 sq ft: the 240 at $199.99. The 400 would be paying for coverage the walls will not let you use.
• A bedroom where you can hear a fan at night: the 130i at $124.99, 27 dB on low and app scheduling so it runs while you are out.
• Anyone who needs a published CADR: none of the three, and only the 240 carries a stated HEPA grade in our catalog. Our best air purifiers guide covers the units that publish the numbers.

Bottom line

The PuroAir 400 is a $324.99 purifier, $279.99 with a subscription, whose only real argument over the cheaper 240 is a 2,000 sq ft rating, and that argument holds exactly when the space is a single large open room. It arrives with no CADR, no stated HEPA grade, and an independent testing record that says to treat the rating as a ceiling, so buy it for the coverage and size up rather than down. For two separate rooms, a pair of 240s at $319 is cheaper and better placed; for a bedroom, the 130i is quieter and less than half the price. If a published performance number is what you need, the answer is a different brand, and the best air purifiers guide has them.