Best Air Purifiers: Breathe Easy And Banish Pollution

Air purifiers are devices that improve indoor air quality by removing pollutants and allergens from the air and replacing them with fresh, clean air. They are particularly useful for people with allergies or asthma, as they can help to reduce symptoms and improve overall health. When purchasing an air purifier, it is important to consider factors such as room size, certifications, ratings, filters, and cost. This article will review some of the best air purifiers on the market in 2025, including the Blueair Blue Pure 211i Max, the Coway Airmega AP-1512HH Mighty, and the Alen Air BreatheSmart 75i, and provide an overview of the features and benefits that make them stand out in the market.

HEPA filters

HEPA stands for High-Efficiency Particulate Air. HEPA filters are highly effective at trapping harmful airborne particles, including allergens and pollutants, thereby improving air quality. They are particularly beneficial for individuals with respiratory issues or sensitivities. HEPA filters can capture up to 99.97% of particles as small as 0.3 microns in size, which is significantly smaller than the width of a human hair, which typically measures between 20 and 180 microns. This makes them ideal for removing dust, smoke, and household odours.

When purchasing a HEPA filter, it is important to ensure compatibility with your air purifier model. Using the wrong filter can reduce the purifier's ability to clean the air effectively. It is recommended to replace HEPA filters every 6 to 12 months, depending on usage and the specific model.

Some air purifiers combine HEPA filters with other technologies, such as carbon filters, to enhance their performance. Carbon filters are particularly effective at eliminating odours and gases, including volatile organic compounds (VOCs). Additionally, some purifiers offer smart capabilities, such as remote or voice control, real-time data, and scheduling features, although these are not essential for effective air purification.

The Coway Airmega AP-1512HH Mighty is a notable air purifier that consistently delivers excellent performance in removing smoke pollution. It has been recognised as a top choice by multiple sources due to its effectiveness, compact form, quiet operation, and display-light shut-off feature.

Allergies and asthma

If you suffer from allergies or asthma, an air purifier can be a great way to help reduce your symptoms. Air purifiers capture virtually all airborne allergens, such as pollen, dust, pet dander, and mould spores, as well as bacteria, viruses, and smoke.

When choosing an air purifier for allergies and asthma, there are several factors to consider. Firstly, room size is important. You'll need a purifier powerful enough to effectively clean the space you have. The Coway Airmega AP-1512HH Mighty, for example, is suitable for large rooms and can clean a 361-square-foot space. Alternatively, the Blueair Blue Pure 211i Max is designed for spaces of around 500 square feet. For smaller rooms, the Honeywell HPA 104 AllergenPlus HEPA Air Purifier is a good option.

The type of filter is another key consideration. HEPA filters, or "high-efficiency particulate air" filters, are a popular choice as they can remove at least 99.97% of particles with a size of 0.3 microns, including dust, pollen, mould, and bacteria. The MERV rating, or "minimum efficiency reporting values", will help you determine a filter's ability to capture particles between 0.3 and 10 microns.

Certifications and ratings are also important indicators of a purifier's quality. The Levoit Core 400S Smart Air Purifier, for example, has a BHG Recommends seal of approval, indicating that it has been rigorously tested. The Levoit also has impressive reviews, with 4.7 stars and over 125,000 ratings on Amazon.

Some other recommended purifiers for allergies and asthma include the Alen Air BreatheSmart 75i, which is sensitive enough to detect and react to incense, and the Blueair small-room 3-in-1 model, which has an easy-to-use app for control. The Winix 5500-2 is another exceptional performer, capturing 99.9% of smoke in a test room in 30 minutes.

While air purifiers can be an effective tool for managing allergies and asthma, it's important to note that they are just one part of an overall strategy for dealing with these conditions.

Cost and value

The Coway Airmega AP-1512HH Mighty, for example, offers great value in terms of initial and long-term costs. With a price tag of under $200, it is an economical choice that delivers high performance and durability. Its energy efficiency further contributes to its long-term value, as it consumes less energy than other models, resulting in lower operating costs.

In contrast, some air purifiers can have high upfront costs. For instance, the Alen Air BreatheSmart 75i, recommended for allergen removal, comes with advanced features such as a child lock and customizable panel designs, but may be more expensive. The HealthMate HM400 is another example of a purifier with a high upfront cost, and its replacement filter costs, energy inefficiency, physical bulk, and noisy operation may detract from its overall value.

When it comes to filter replacements, the frequency and cost can vary. Activated carbon filters, for instance, need to be replaced more often, especially in environments with heavy air pollution, and can cost up to $50 each. On the other hand, washable air filters offer a more cost-effective solution, eliminating the need for frequent purchases of new filters.

Additionally, it's worth noting that some air purifiers with advanced features may carry a higher price tag. For example, the Coway Airmega 250 Smart Air Purifier, with its auto mode and LED light modes, may be more expensive than basic models. The Blueair Blue Pure 311i Max, known for its excellent purifying performance, also falls into this category of advanced purifiers with a potentially higher price.

In summary, when considering the cost and value of air purifiers, it's important to look beyond the initial purchase price. Factors such as energy efficiency, filter replacement costs, and the inclusion of advanced features can significantly impact the long-term value of an air purifier. By weighing these considerations, you can make an informed decision that balances performance, convenience, and cost-effectiveness.

Air quality indicators

One of the most commonly used indicators is the Air Quality Index (AQI), which is the EPA's tool for communicating about outdoor air quality and health. The AQI consists of six colour-coded categories, each representing a range of index values that signify the level of air pollution and associated health concerns. For instance, an AQI value of 50 or below indicates good air quality, while a value over 300 represents hazardous air quality.

Some air purifiers, such as the Coway Airmega 450, feature built-in air quality sensors that illuminate an indicator light to convey indoor air quality. However, the colour coding on the Coway Airmega 450 does not follow the standard AQI colour code, which may confuse users. For example, the light glows green for moderate air quality, which is inconsistent with the AQI colour code where green represents good air quality.

Other air purifiers, like the Alen Air BreatheSmart 75i, feature an air quality ring that changes colour when it detects allergens or pollutants. This provides a visual indicator of the presence and level of pollutants in the air.

In addition to visual indicators, some purifiers offer digital displays that provide information about air quality. For example, the Levoit air purifier features a digital display and an app that allows users to monitor air quality, set timers, and check the life of the filter.

When selecting an air purifier, it is important to consider factors such as room size, certifications, ratings, and the type of filters used. The effectiveness of a purifier in reducing pollutants is a key indicator of its quality.

Room size

When choosing an air purifier, room size is a crucial factor. The effectiveness of an air purifier is influenced by the size of the room and the volume of air it needs to purify.

For example, the Blueair Blue Pure 211i Max is designed for large spaces of around 500 square feet. It is a powerful purifier, reducing smoke levels by more than 99.9% on its high and high-medium settings, and it is also energy-efficient and quieter than expected for its size.

On the other hand, the Coway Airmega AP-1512HH Mighty is a good choice for smaller spaces. It can clean a 361-square-foot room, exchanging the air 4.8 times per hour when operated at its highest and loudest setting. If you want to run it at a quieter setting, it is recommended for a room of around 200 square feet or smaller.

The Blueair small-room 3-in-1 model is another option for smaller spaces. This model was tested in a 200-square-foot bedroom and features oscillation, as well as built-in heating and cooling functions.

The Levoit Core 400S Smart Air Purifier is another option that can be purchased on Amazon for $220. It is effective at removing pollutants, as well as improving allergy symptoms.

When considering room size, it is also important to look at the number of air changes per hour (ACH). A minimum of four ACH is recommended for a purifier to adequately clean the air in a room. This ensures rapid and nearly complete cleaning of highly polluted air.

Additionally, the Clean Air Delivery Rate (CADR) is a factor to consider when choosing an air purifier. CADR measures the volume of air purified in a set amount of time and is calculated in cubic feet per minute or cubic meters per hour. This can help determine the efficacy of an air purifier for a given room size.

Frequently asked questions