Every convenience in life comes at a cost. That's why things are so expensive at the corner store compared to the grocery store. They aren't selling you a carton of milk, they're selling you a way out of a mistake in not remembering to pick up your milk early at the supermarket. That kind of convenience has a readily tangible cost - more money out of your wallet. The convenience cost of other things, such as technology, might not be so readily apparent.

Take for instance RFID chips. These are Radio Frequency IDentification chips. You'll probably be most familiar with them by seeing them on your bank cards or credit cards. These chips are being used as a replacement for the once ubiquitous magnetic stripe. By using RFID on these cards instead of the stripe, the convenience we gain is that they are less susceptible to damage, and don't need to be run through a strip reader which has its own problems. How often have you had to run a card through three or four times per transaction? It's a pain compared to just tapping the card reader. The RFID chips can also store more information and have that information encrypted, supposedly for your safety.

Like every new technology that comes along, intended to keep us and our information safer, there are legions of people out there willing to show is that it isn't always safe. Really though, what is 100% safe? Nothing - we just have to have an acceptable level of security and, for all intents and purposes, RFID tags are reasonably secure. Yet, they can still be surreptitiously read, decoded, and used in crimes against you.

You may have seen videos of people using card readers bought online to brush up against a purse or wallet, thus harvesting the information from the RFID tags inside. In fact, what you see below is an RFID reader kit, called RFIDuino. Then the person takes that harvested information to their lair of evil and decrypts information to literally make copies of your bank or credit cards. At which point the Rolex shopping spree begins and you get stuck with the tab.

how to block rfid chips

It doesn't have to be this way. The odds of it actually happening to you in the first place are extremely slim. However if you want to protect yourself a little further, there are some very easy things you can do. Remember, the R stands for Radio, so anything that louses up your music radio's reception is going to have a similar effect on these little things. If you want to understand how RFID chips work, check out this article.

Where Did It Go?

For people who carry a wallet in the back pocket of your pants, you can easily switch to putting it in your front pocket. This has two positive outcomes. One is that it makes it harder for someone to brush up against you with a reader. Most people react very differently when getting bumped in the groin area than getting bumped on the bum. This may be enough deterrent for most would-be thieves.

The other benefit is that it's better for your back to not have lumpy wallets throwing off the alignment of your spine when sitting. There are even commercially available front-pocket wallets with RFID blocking built in, like the one below.

how to block rfid signal

If you carry a purse or handbag, you may consider not keeping your bank cards in it, but perhaps in something that is going to be on your body where you will naturally have higher vigilance against contact. If you need to keep it in the handbag, keep it in the innermost compartment of your handbag, in a wallet. All the other stuff in your bag could create enough interference to stymie the card reader.

Keep in mind neither of these methods is a 100% foolproof. They only make the likelihood of the card being read much less.

What's IN Your Wallet?

No, really, what is in your wallet? Is it just a leather or fabric wallet? These don't lend much stopping power against radio waves. There are commercially available wallets that are lined with aluminum or other metallic foils that help interrupt radio waves. But you can get a similar effect by lining your wallet with foil. There are dozens of ways you can do this and dozens of sites that show you how. If you have a wallet that has a billfold slot, the easiest thing you can do is to insert a sheet of foil there. Once the wallet is closed everything inside is protected by the foil.

You could also get a similar effect by using an anti-static bag - you know the kind that some computer hardware is shipped in. Those are somewhat similar to a Faraday Cage. All the other methods are simply fancier variations on this.

What IS Your Wallet?

You can step it up a notch and find a metal container to store your cards in. Again, there are various manufactured ones specifically designed for this purpose, or you can re-use some other item for the job. The always-popular Altoids tin works. Some people also use cigarette tins for this purpose. You might even use a tin that was used to hold playing cards. All of those introduce a metal shell that helps defeat radio signals.

how to block rfid signal

Why Bother With RFID?

"Couldn't I just pry the darn thing off the card? I mean, I've already got the magnetic strip there, that should suffice." Oh if only it was that easy.

The card is not your property. If you read your contract, I'm sure you'll find that the cards remains the property of the bank or company that issued it. So you'd be damaging someone else's property. You may find that doing so invalidates your card completely. However, you might want to call the card issuer and see if they will issue you a stripe-only card. They might or they might not. You won't know until you ask.

What Will Work 100%?

Forgo the convenience of having a bank or credit card to pay for things and only carry cash. Of course, that introduces its own set of problems. But if you feel strongly enough about it, it's not a bad way to go. Carrying only cash has a nice benefit of limiting what you spend to what you have on you and cuts back on impulse purchases.

The next closest thing is to have an actual Faraday Cage for your cards, not just some tinfoil. Faraday Cages are specifically designed mesh-like metal holders that essentially filter out certain electromagnetic frequencies and siphons them off to the ground. This means that you'd have to know what specific frequency your RFID tags operated on and have the appropriate cage for that.

You would also need a grounding strip going from the cage to the ground. It doesn't sound very practical now does it? You'd be like one of those cars with the motion-sickness strip coming off the bumper and hitting the road. Maybe that'll be the new fashion trend someday.

how to block rfid chips

In short, nothing will work 100% to eliminate the possibility of your RFID cards being scanned. All you can do is use or or more of the techniques above to limit the risk a little more. Also use your situational awareness. Keep an eye out for someone who just keeps bumping into people. Look for card readers that seem to have more things attached to them than they should. Don't just hand your card over to a waiter and let them walk to the card machine with it. Treat your card like you would with cold hard cash - because it is.

I hope you feel more empowered now about the safety of your credit and debit cards. Maybe you feel  a little wiser but don't be disheartened. People are essentially good.

If you got something from this, I'd sure like to hear about it in the comments below. It's also a great place to share any additional stories or tips that you might have. Remember, we're all in this together.

Image Credit: Client Card Sample via WikiCommons, RFIDuino via illustir on Flickr, Altoid tin via WikiCommons, Faraday Cage via WikiCommons