Listen and follow The Wirecutter ShowApple Podcasts | Spotify | Amazon Music | YouTube | iHeartRadioThis week, we’re re-airing a discussion about keeping your indoor air clean and healthy to breathe. Wirecutter senior writer Tim Heffernan walks us through how to reduce the outdoor pollution that inevitably seeps into your home, what to do if you're dealing with wildfire smoke, and surprising and free ways to keep your air clean.Tim covers exactly why you shouldn’t overspend on an air purifier, and how often you really need to change the filter. Plus he does some myth busting about whether plants clean the air.This episode covers:Monitoring outdoor air: How to use the free EPA Air Now app to track local Air Quality Index (AQI) levels, so that you know when to wear an N95 mask or seal up your home.Wildfire preparedness: Practical, low-cost steps to prevent outdoor smoke from contaminating your indoor air, from adjusting your HVAC settings to designated shoe-and-clothes drop zones.Air purifier science: How HEPA filters capture microscopic particles, why you don't need to replace filters as often as manufacturers claim, and where to position your unit for maximum coverage.Gimmicks to avoid: Why plants won't clear wildfire smoke and why expensive non-HEPA technologies fail Wirecutter's rigorous testing.Products we recommend:The best indoor air quality monitor AirGradient OneAirGradient OneWith an easy-to-read physical display and user-friendly web dashboard, the One can help you identify, track, and correct air quality concerns indoors.Buying options: $230 from AirGradient, opens in a new tabBest app for basic monitoring AirNowAirNowThe EPA’s free AirNow app is easily searchable, delivers air quality readings in almost every corner of the US, and lets you know in advance of upcoming air quality problems.Buying options: Buy from Apple App Store, opens in a new tab(free)Buy from Google Play, opens in a new tab(free)Buy from AirNow, opens in a new tabThe best air purifier of 2026 Coway Airmega Mighty2 (AP-1512N)Coway Airmega Mighty2 (AP-1512N)The Coway Airmega Mighty2 out-performs its predecessor, making it our first new top pick in a decade. It’s more energy efficient, quieter, and easier to maintain. And it’s nicer looking, too.Buying options: $270 from Amazon, opens in a new tab$270 from Wirecutter Store, opens in a new tabFree ShippingAnother great air purifier Coway Airmega Mighty (AP-1512HH)Coway Airmega Mighty (AP-1512HH)Perfect for bedrooms, playrooms, and living rooms, this purifier is one of the highest-performing, most-durable, and most-economical models we’ve tested.Buying options: $230 from Amazon, opens in a new tab(white)$230 from Amazon, opens in a new tab(black)$230 from Walmart, opens in a new tab(white)$230 from Walmart, opens in a new tab(black)$240 from Wirecutter Store, opens in a new tabFree ShippingA great pair of pliers Knipex Carpenters’ End Cut PliersKnipex Carpenters’ End Cut PliersThe Cobra’s self-locking feature is flawless, and its 25 different settings give you more nuanced jaw-width options than competitors do.Buying options: $42 from Amazon, opens in a new tab$36 from Zoro, opens in a new tab