What are Faraday boxes all about? That’s a good question. It does sound like the kind of thing HG Wells might have used to get his time machine going, but it is actually an invaluable car security device that can protect your car from the threats posed by keyless car theft.
Most vehicles are now equipped with keyless entry and ignition, operated by electronic signals from your key fob (RFID). However, Mr Thief and his friends have caught up with advances in security technology impressively quickly, and it’ll come as no surprise that there is a way to intercept and clone those electronic signals enabling the theft of your vehicle, even if your car fob is sitting apparently secure inside your home on the hallway table.
But, adding an extra layer of car security and preventing those radio signals from being intercepted is easy and reasonably inexpensive. A Faraday pouch or box is simply a small, domestic, practical Faraday cage. The box is lined with a metallic material which prevents any electronic signals from entering or leaving the box, thereby preventing would-be thieves from intercepting your RFID signals and stealing your car.
Keyless vehicles can be stolen and driven away in under a minute with the right techniques, so as a car owner it’s a no-brainer that blocking the signal is one of the easiest things for you to do to prevent your car theft. So, when you get home, don’t just leave your fob on the table; put it safely in a Faraday box. It’ll keep your car safe, and you’ll have no more misplaced keys.
The best Faraday boxes 2025 at a glance
What is a Faraday box, and is it essential?
A Faraday box (or Faraday cage) is a container made from conductive materials, often metal, that blocks electromagnetic fields. It works by redistributing electrical charges or radiation around the outside of the box, preventing them from reaching the inside. Most modern car keys emit radio signals even when not in use, so thieves can use signal boosters to trick the car into unlocking or starting. It all sounds kind of complicated, but a Faraday box effectively blocks these signals and is another tool to help prevent your car from being stolen.
A Faraday box isn’t essential for everyone – for example, if your car doesn’t have keyless entry, you don’t need one. But if you have a keyless car or care about blocking signals for privacy or protection, it’s an affordable and effective safeguard.
The best Faraday boxes 2025
Tested product
Editor's choice
The Vonetti box is an ideal dual-purpose Faraday box. It's great when you're out and about, although I did find it a bit heavy when I put it in my trousers pocket. It's not an issue in a coat or jacket pocket or bag. It is unobtrusive when you're at home, and you can just leave it where you would normally leave your key fob.
As far as performance goes, I can't fault it. When I approached my car and tried to enter, it remained locked. After manually unlocking the car and getting in, when I pressed the start button, the car told me that no key was recognised in the vehicle. Job done.
Review by Alex Boyd
Pros
- Stylish design and a premium upgrade over a conventional pouch
- Compact enough to take with you and carry it in a large pocket
- Quality construction and durable materials
Cons
- Only suitable for a single fob rather than multiple units
Tested product
The best Faraday box
You'll also receive a sturdy Faraday pouch, which will comfortably accommodate most key fobs with a key ring attached. Perfect for keeping your signal hidden while you are away from home.
I tested the box by approaching my car with both the main and spare key fobs in the box (double the signal? I'm not sure). No matter, when I tried to open the door, it remained securely locked. I removed the fob from the box to get into the car. Once inside with the key safely back in the box, I was unable to make any further progress as no key was recognised.
Review by Alex Boyd
Pros
- Good finish
- Ideal size for the average family
- No catch on lid so it opens easily
Cons
- Gets a bit crowded with more than two fobs
Tested product
Best large Faraday set
Faraday boxes can’t help with the former problem – speaking from experience, once a thief is in your house, they’ll tear it apart until they find your keys. However, they can stop the second method dead in its tracks. These small boxes block your keys’ RFID signal and prevent it from being cloned. And the Mosfiata Faraday Box is quite a good one.
The BMW M135 I’m currently driving has keyless entry, so I’ve been able to test whether the car can read the signal from my keys when they’re in the box, and it can’t. This Faraday box from Mosfiata completely isolated them from the world, and because it’s so large, it’s got plenty of space for all your family’s car keys. The only problem I can see is finding somewhere inconspicuous to hide it.
One other thing I should note is that the Faraday pouches that come with the box don’t work in the slightest. I put my car keys in one, unlocked it through the pouch, and the car dutifully opened its doors. My advice? Bin the pouches and just throw your keys in the box. They’re too small for most modern car keys anyway.
For maximum security, team this Faraday box with a steering wheel lock and a home security camera. That way, you’ve got another physical deterrent for thieves, but if they’re the persistent sort, you’ll be able to catch them in the act.
Review by Luke Wilkinson
Pros
- Comes with additional pouches, which are fairly sizeable themselves
- Large enough for six fobs, which is great if you have a fleet of vehicles
- You can choose between a small or large size box
Cons
- The pouch can be a bit tight for some fobs
Wall-mounted Faraday box
Tested product
Best wall-mounted Faraday box
That said, I do like the metal doorknob that looks and feels expensive, the faux stitching is a nice touch, and I truly appreciate the size of the box. The four felt-covered hooks are spread widely apart and had no issue dealing with a large, modern car key with a selection of house keys and an unnecessarily bulky Hot Wheels keyring I insist on using attached. My experience of slimmer key boxes suggests this isn’t always the case.
I appreciate that it comes with four pre-drilled holes, four screws and even four wallplugs to mount it, but they seem rather pointless as the box has no form of lock at all. There are magnets to keep the door closed, but a final layer of protection is something both my wife and I thought was missing.
Even with those holes present and unfilled by screws, the box does work faultlessly. Even holding the box right next to the BMW M5 I’m currently driving, the car refuses to unlock until I open the lid of the Faraday box. That suggests to me that anybody looking for a key fob signal to clone will also be right out of luck.
I suspect most people will be better off with one of the smaller, cheaper and just as effective Faraday boxes in this list. However, if you’re in the fortunate position of having four new or nearly new cars with big, bulky key fobs, this is well worth considering.
Review by Alan Taylor-Jones
Pros
- Lots of space inside for all the family's keys
- Ready to wall mount with drilled holes, screws and plugs included
- Looks relatively classy once with its faux leather finish and stitching
Cons
- Requires fitting, which may put some off
- Isn't the most versatile option, thanks to vertical design
Tested product
Best value Faraday box
The leather feel of the outside is a plus point, too. It feels like a homely item, and if you're after that sort of thing, this is pretty ideal. I would prefer it to be larger on a personal level; car key fobs are huge nowadays (Maserati is leading the way), so it would be nice if you could fit multiple large fobs into it.
Overall though, I like it. And I like the fact it's not too much money either - meaning it really does take a small step to protect your pride and joy.
Review by Aaron Hussain
Pros
- Compact, but can still fit up to four key fobs
- Decorative look and can be had in either brown or black
- Represents better value for money than some of the others at under £20
Cons
- Quality of the latch could be improved
- No pouches included, so no portable protection as well
Recommended
Best large Faraday box
The brand says the box can fit up to nine sets of keys, which is perfect if you want to store multiple keys and items inside. There's even space for some phones, which helps if your vehicle is keyless from your device.
Pros
- Box is large enough for up to nine sets of keys
- Includes two fobs, which is great considering the price point
- Subtle design that will blend in with your home furniture
Cons
- They key pouches aren't the strongest on the market
Recommended
Best box and pouch combo
Pros
- Attractive finish and looks subtle in your home
- Pouches included for added protection on the go
- Compact yet spacious design, which means clever packaging
Cons
- Pouches can be a tight fit for larger fobs
Faraday boxes FAQs:
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What is a Faraday box or a Faraday cage?
A Faraday box or Faraday cage is a container made of conductive materials that shields its contents from electromagnetic fields. It works because the conductive material redistributes electromagnetic waves around the external surface, preventing them from reaching the inside. In the case of a Faraday box for car keys, it works in reverse by keeping the key fob radio signals within the box. The cage can block various forms of electromagnetic radiation, such as radio waves, microwaves, or electromagnetic pulses (EMPs).
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Do Faraday boxes work?
Yes, Faraday boxes do work. They effectively block external electromagnetic fields from penetrating their interior, provided they are made of conductive material, have no gaps or openings, and are sealed properly. When used correctly, they can shield electronics from potential threats like hacking using RFID scanning equipment. However, the effectiveness can vary depending on the quality of the box. Higher-quality Faraday boxes provide better protection against a wider range of signals.
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Are Faraday boxes worth the money?
Whether Faraday boxes are worth the money depends on your needs. In the UK, Faraday boxes are increasingly popular among those who want to protect their devices (like mobile phones, credit cards, or key fobs) from hacking. If you’re concerned about security or privacy, a Faraday box could offer peace of mind, particularly for high-value electronics or important documents that may be contained on a flash drive or similar. If you have few electronic devices, use a 'dumb' phone and don't have remote locking on your car, a Faraday box may not be strictly necessary.
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Do I need a Faraday box?
If you have any concerns about any of the following, it is probably worth your while investing in a Faraday box.
Security: If you’re worried about privacy and electronic tracking (e.g., someone accessing your key fob, phone or credit card information via RFID), a Faraday box can block those signals.
EMP Protection: While the UK is not a primary target for EMP threats, people living in regions with high electromagnetic interference or worried about large-scale disruptions might consider having a Faraday box as a precaution.
Protecting Devices: If you have valuable electronics that are at risk of hacking, jamming, or being damaged by external interference, it might be worth investing in a Faraday box.
For most people, it’s not a necessity but it is a good addition to your security measures. -
How to test a Faraday box?
To test a Faraday box, you can conduct the following tests:
Mobile phone test: Place your mobile phone inside the box and try calling or texting it from another phone. If the box is working, the phone inside should have no signal and should not be able to receive calls, texts, or data.
RFID test: Simply put your car key fob into the Faraday box, then take the closed box to your vehicle and see if the key fob is detected by your car's electronics. Alternatively, you can put an RFID-enabled device (like a contactless payment card) inside the Faraday box. Try scanning it with a contactless card reader. If the box is effective, the card should not be detectable or readable by the scanner.
Wireless signal test: For a broader test, place a device that uses Wi-Fi or Bluetooth inside the box. Try to connect to it from another device. If the Faraday box is working, you should not be able to establish a connection.
How we choose Faraday boxes
All of these Faraday boxes have been hand-selected by our team of experts, who have spent hours investigating and researching Faraday boxes to make it easier for you to find the very best, and we’d never recommend a product we don’t believe in. Where possible, we also test and share the latest and best products you should know about.
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