You’re here for one of two reasons. Either you’re wondering what a Faraday bag is, or you want to know why you should buy one. And you’re going to get the best answers to both.


Michael Faradayis the scientist who conducted pioneering research on electricity in 1836 which led to his signature invention, the Faraday cage.


A Faraday bagis a type of Faraday cage. It protects electronics from being damaged by radio frequency interference (RFI) or from an electromagnetic pulse (EMP) by not allowing radio frequency or electromagnetic pulse waves to pass through the material. It goes by a lot of names such as RFID bag, RFID blocking bag, EMP bag.


How a Faraday bag worksis it creates a completely enclosed space that is surrounded by a mesh of conducting materials. When an electrical field on the outside of the Faraday cage interacts with the material, it causes the charges within the protected space to be distributed in a way that cancels the effects. It also works to protect against radio frequency interference.


The threats that a Faraday bag protects againstcould be naturally occurring, or manmade. An example of a naturally occurring threat is a solar storm. Believe it or not, solar storms which come from the sun have the potential to wipe out power grids and electronics here on earth. One such storm is known as the Carrington Event, and occurred in 1859. At that time, humanity didn’t have nearly the level of reliance on electronics that we do today. Yet at that time, telegraph systems in Europe and North America stopped working, the equipment sparked and gave shocks to the operators and even started fires.  If a solar storm of this magnitude were to occur today, it would widely damage and disrupt electronics such as cars, computers, and power grids. Even smaller items might be affected such as a common USB drive. Such a solar storm occurred in 2012 of a similar magnitude but it didn’t hit earth (it missed by just 9 days).

In 1989, another solar storm hit the Earth and Canadians took the brunt of it, although it wasn’t of the same magnitude as the Carrington Event. Still, power grids went offline and some 6 million Canadians were left without electricity - some for hours and some for days.

As it happens, there is no reliable way to predict solar storms or when they may happen.


Man-made threats are predicted to come in the form of nuclear or EMP bombs. Nuclear explosions send out electromagnetic shockwaves that could wipe out electronics and power grids just like solar storms. A man-made bomb that emits electromagnetic shockwaves could even be detonated some distance above a target in order to be effective. This topic was even brought up among GOP presidential candidates during the 2016 election race.

The fact is that, despite the possible threat to electronics, people and nations are not prepared to defend the technology that we are becoming increasingly reliant upon.


So what does that mean for Bitcoiners? Why is it all the more important for us to consider such threats and take appropriate measures? And is it an ‘appropriate measure’ to get a Faraday bag?



If you’re a Bitcoiner with any significant amount of Bitcoin, or if you’re a Bitcoiner who ever intends to have a significant amount of Bitcoin, then it is absolutely worth it to get a Faraday bag.


Common objections to owning a Faraday bag are that it’s unnecessary if you have your mnemonic seed (private keys) backed up on your Billfodl already, and that the likelihood of an EMP blast is low enough that you don’t want to spend the money.


The risk-reward ratio of owning a Faraday bag is heavily tilted in favor of getting one. The probability of the risk may be low (or it may not be), but the cost of a Faraday bag is also very low. It simply doesn’t make sense for a Bitcoiner to argue that the world should be supported by a digital monetary system that allows individuals to be completely sovereign over their money, and then on the other hand to argue that individuals who do so should be careless enough not to protect valued electronic devices which greatly enhance the security of accessing said money.


So you have a Billfodl already. That definitely is a higher priority than owning a Faraday bag, EMP bag, RFI blocking bag. And if our electronics do go down due to some form of disaster, Bitcoiners will not have access to their funds unless they also have access to functioning electronics that can be used to interact with the bitcoin network. And in such a case, if a Bitcoiner should have to use an untrusted computer to access funds, simply using the private keys could be a very risky endeavor and should be avoided. If only that Bitcoiner had stored a tablet or Bitcoin hardware wallet in a Faraday bag, all would be well.


Faraday bags protect more than just hardware wallets and USBs. The Cheshire Police in the UK are recommending drivers to keep their car keys in a Faraday bag to prevent thieves from being able to clone them. All they would need to do is get close to your keys, without even seeing them, unless they were protected in an RFI-blocking Faraday bag.

Here are some items that might be worth protecting by keeping them inside a Faraday bag:

·         Keys

·         USB

·         Bitcoin hardware wallet

·         Phone

·         Tablet

USBs and Bitcoin hardware wallets will fit inside Billfodl’s smaller Faraday bag. If you want to keep a phone or small tablet, you’ll want to get the bigger one



On the Let's Talk Bitcoin podcast, Andreas Antonopoulos stated that he kept his hardware wallets in a faraday bag. In addition, @patrickwagner, a digital security expert, calls a Faraday bag “a must have.” The threat of a solar storm or EMP blast to our society presents itself as one of the greatest dangers to security in any modern country. If we are going to digitize our monetary system at any point in the foreseeable future, it’s time to take proper security measures to protect our assets today. 

2 Responses


January 30, 2020

This is actually a question. Do bags protected against RFID scanning offer protection similar to faraday bags from EMP?

James Pearson
James Pearson

January 08, 2020

Dear Sirs,
Will a faraday wallet conceal $US bills inside when putting it though airport security

Leave a comment

Comments will be approved before showing up.