Break Out the Tinfoil: How to Make Your Own Faraday Cage
Whether you want to keep your devices secure during a protest or are just prepping for doomsday, here's how to shield your gadgets from electromagnetic fields.
Home How-To Weekend Project Break Out the Tinfoil: How to Make Your Own Faraday Cage Whether you want to keep your devices secure during a protest or are just prepping for doomsday, here's how to shield your gadgets from electromagnetic fields. By Chandra Steele Chandra Steele Senior Features Writer My Experience My title is Senior Features Writer, which is a license to write about absolutely anything if I can connect it to technology (I can). I’ve been at PCMag since 2011 and have covered the surveillance state, vaccination cards, ghost guns, voting, ISIS, art, fashion, film, design, gender bias, and more. You might have seen me on TV talking about these topics or heard me on your commute home on the radio or a podcast. Or maybe you’ve just seen my Bernie meme. Read Full Bio Updated April 30, 2024 Threads Bluesky Reddit Social Share Facebook LinkedIn Pinterest Flipboard Twitter Copied Error! Copy Link https://www.pcmag.com/how-to/how-to-make-your-own-faraday-cage Email Comments (Credit: Zain bin Awais) If you're looking to shield yourself or your devices from electromagnetic fields, a Faraday cage is a potentially useful tool. Use it to prevent thieves from messing with your car key fobs, block NSA eavesdropping (maybe), or just live out your doomsday prepper dreams as you wait for a gigantic, Earth-enveloping electromagnetic pulse to wipe out all electronic communication.You can buy Faraday cages that vary in size from small bags that hold a smartphone to a Faraday tent under which you can park a car and probably your entire family.Think you can cook up a solution in your own kitchen using appliances? It's not that easy. A refrigerator or freezer is commonly thought of as an ersatz Faraday cage, but unless the seal is tight, it probably won't work. Likewise, a microwave oven does not a Faraday cage make. You May Also Like Still, some home items can be converted into a Faraday cage at little cost. Before you put your phone in one, though, put it in airplane mode to avoid battery drain as it searches for a signal.Think SmallIf you're making a Faraday cage for on-the-go, your best bet is to buy one. But you can make a small one. The tinfoil hat joke comes from somewhere, and that somewhere is the Faraday cage. Aluminum foil can be used to protect against electromagnetic fields. Shoplifters use this to their advantage by coating the inside of bags to prevent detection. The same principle applies to this guide on Instructables about using aluminum foil, an envelope, and some tape.File It AwayA metal file cabinet requires a few tweaks to be turned into a Faraday cage. These directions on Instructables require just a few common pieces of hardware, some cables, and the cabinet itself.This Is All GarbageThe solution could be in your own backyard. Metal garbage cans—with a bit of modification—can be effective Faraday cages. Recommended by Our Editors How to Send an Anonymous Email 10 Essential Apps for Ironclad Online Privacy in 2026 Does Your Airbnb Have Hidden Cameras? Here's How to Check Shake It OffIf all this talk of Faraday cages is stressing you out and you want a drink, stop! Your easiest solution is at hand with a cocktail shaker. Testing 1-2-3Whatever Faraday cage you choose, test it. Rigorous testing involves a software-defined radio receiver but you can do a simple test by tuning a radio to a station that comes in strong and placing it inside the Faraday cage. Close the cage and if you can still hear the station, the cage is not working. About Our Expert Chandra Steele Senior Features Writer Experience My title is Senior Features Writer, which is a license to write about absolutely anything if I can connect it to technology (I can). I’ve been at PCMag since 2011 and have covered the surveillance state, vaccination cards, ghost guns, voting, ISIS, art, fashion, film, design, gender bias, and more. You might have seen me on TV talking about these topics or heard me on your commute home on the radio or a podcast. Or maybe you’ve just seen my Bernie meme. I strive to explain topics that you might come across in the news but not fully understand, such as NFTs and meme stocks. I’ve had the pleasure of talking tech with Jeff Goldblum, Ang Lee, and other celebrities who have brought a different perspective to it. I put great care into writing gift guides and am always touched by the notes I get from people who’ve used them to choose presents that have been well-received. Though I love that I get to write about the tech industry every day, it’s touched by gender, racial, and socioeconomic inequality and I try to bring these topics to light. Outside of PCMag, I write fiction, poetry, humor, and essays on culture.Making incomprehensible tech news easy to understandExpanding the boundaries of topics covered in the industryFiguring out tips and tricks in apps and on devices and letting you know about themPutting together gift guides for everyone in your life All that gadgets is gold for me: my iPhone 11 Pro, my fift...