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How to Make Your Own Air Purifier

Posted on July 8, 2024   |   Updated on September 30, 2025
Adrian González

Adrian González

A person building a DIY air purifier on a table.

Save money (and your lungs) with a DIY air purifier. (Michael Robinson Chávez / The Washington Post via Getty)

After a weekend of fireworks and race cars zooming through the streets of Chicago, air quality might not be at its best. Air purifiers can help, but they can be expensive. Here’s how you can make your own at home with a few simple items.

🧰 Quick and Simple

Necessity is the mother of invention, so let’s start with the most simple version of a DIY air purifier.

  • Step 1: Acquire a square fan (most air filters are squares or rectangles, so we’re applying basic geometry).
  • Step 2: Get yourself a HEPA filter (shoot for one similar in size to your fan).
  • Step 3: Secure the filter to your fan via duct tape or packing tape, making sure to seal the connection as tightly as possible.

▶️ Follow along with this tutorial from the New York Times’ Wirecutter. Their testing showed this simple version outperformed a fancy $800 air purifier!

👷 Take it to the Next Level

After covering the COVID-19 pandemic, Washington Post reporter Lena H. Sun took it upon herself to build what’s called a Corsi-Rosenthal Box, which basically takes the version above and gives it superpowers. She has a great step-by-step guide on how to build one.

How to Check Chicago’s Air Quality
see more:public health

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