Best Air Purifier of 2025

In-Depth Testing of Air Purifiers at CNET Labs

At the CNET Labs product testing facility in Louisville, Kentucky, we conducted a comprehensive evaluation of 14 popular air purifier models. The goal of this rigorous testing was to assess which air purifiers offered the best performance in terms of particle removal efficiency, energy consumption, and quietness, while also evaluating their features and overall value. By subjecting these devices to a series of controlled tests, we aimed to provide consumers with actionable insights to help them make informed purchasing decisions.

The Particle-Removal Test: Understanding the Threat of Airborne Particles

The air we breathe is a complex mix of particles, some of which are human-generated—such as emissions from vehicles and industrial activities—and others that occur naturally, like smoke from wildfires or volcanic activity. According to the EPA, microscopic particles, including PM10 (particles less than 10 micrometers in diameter) and PM2.5 (particles less than 2.5 micrometers in diameter), pose significant health risks. These particles are small enough to be inhaled deep into the lungs and can even enter the bloodstream, leading to serious respiratory and cardiovascular issues. Dr. Zhao emphasized that these particles are the number one environmental risk factor globally, contributing to the deaths of 6 to 7 million people annually. Our testing focused on how effectively air purifiers could remove these harmful particles from the air.

Custom Testing Chamber and Smoke Bomb Setup

To simulate real-world conditions, we created a custom air purifier test chamber with a clear plexiglass front panel, gloved hand access, and a particle counter holder. Fans inside the chamber ensured proper mixing of the air, while vent ports maintained a small amount of fresh air. An ignition port allowed us to light custom smoke bombs from outside the chamber, and an exhaust port safely removed remaining smoke after each test. The chamber was not hermetically sealed but was designed to prevent hazardous smoke from escaping. Our custom smoke bombs were made of a mixture of 50% potassium nitrate, 40% sucrose, and 10% sodium bicarbonate, which burned slowly and evenly to create a consistent particle-saturated environment. Using the Temtop PMD331 Particle Counter, we measured particle concentrations, ensuring each air purifier was exposed to roughly the same particle levels to assess their efficiency.

Measuring the Impact of Air Purifiers in Real Time

Once the chamber was filled with smoke, achieving particle concentrations of over 580 million particles per cubic meter, we activated the air purifier being tested. The Temtop device allowed us to track the particle count in real time, giving us precise data on how quickly and effectively each air purifier reduced particle levels. This test was crucial for understanding how well each model performed under controlled, high particle conditions. By recording data every 15 seconds, we could analyze the air purifiers’ performance with unmatched accuracy.

Noise Level Testing: A Key Consideration for Home Use

In addition to particle removal, we also evaluated the noise levels of each air purifier at low, medium, and high fan settings. Using a decibel meter in our sound-enhancing studio, we ensured that only the air purifier’s noise was measured, isolating it from other external sounds. This test was particularly important for consumers who plan to use their air purifiers in bedrooms or other quiet spaces, as excessive noise can disrupt sleep and daily activities. By measuring the decibel levels at different settings, we could assess which air purifiers were the quietest and most suitable for various environments.

Energy Consumption: Understanding the Cost of Clean Air

Finally, we measured the energy consumption of each air purifier using a Kill-a-Watt device. This test helped us understand how much power each model consumed at different fan settings, which is essential for consumers who are mindful of their energy bills. By quantifying the energy draw, we could provide insights into the long-term cost of owning and operating each air purifier. Combining this data with the results from our particle removal and noise tests allowed us to evaluate the overall value of each model and recommend the best options for different needs and budgets.

Conclusion: Finding the Right Air Purifier for Your Needs

Through our rigorous testing, we assessed 14 air purifiers based on their ability to remove harmful particles, their noise levels, and their energy consumption. By conducting these tests in a controlled environment, we aimed to provide a clear and unbiased comparison of the models. The results of our testing will help consumers make informed decisions when choosing an air purifier that meets their needs for clean air, quiet operation, and energy efficiency. Whether you’re prioritizing performance, budget, or convenience, our findings offer a comprehensive guide to selecting the best air purifier for your home.