There have been several theories on the ability of aluminized foil to prevent GPS tracking and communications.
Some claim it can be used as a component in blocking such signals, while others maintain it is worthless for the job. So, does aluminum foil block GPS tracking?
We will attempt to present some of the facts surrounding this topic and let you decide what best suits your needs based on your situation.
Does Aluminum Foil Block GPS Tracking?
First, let’s start with some background on the foil in question. This foil is generally known as aluminized HVAC tape, or aluminized mylar tape, and comes with a paper backing so it can be cut to size for your particular needs.
The most common use would be to block satellite signals (GPS, Satellite Radio, MSS, etc.) from entering the cabin of your car. There are several DIY articles on the internet along with countless videos showing how to apply this foil to your vehicle windows for this purpose.
Some claim it can be used on cell phones and laptops as well, but the signal strength is different in these devices than that of a GPS device and we will not attempt to cover that use in this article.
Before getting into the “facts” of this, let’s take a step back and look at why such devices need blocking or attenuation, to begin with.
Why Block GPS Signals?
The signals used by GPS/MSS (telephone)/Satellite Radio devices are line-of-sight microwave signals. These signals are line-of-sight because they travel in a straight line from the device to the receiving station.
Such signals become attenuated (weakened) the more they have to penetrate or pass through foreign material, such as metal or water.
In most cases, there is very little waves penetration, and most of the signal is reflected off the surface. However, there are certain instances where penetration becomes necessary for these signals to be received by the device.
The first instance occurs inside buildings or parking garages where the signal has to penetrate multiple walls and/or floors to reach its intended destination.
The second is in situations where the receiving device is mounted very low on your vehicle. Even when this condition exists, a strong line-of-sight signal can still be received by the device if it is high enough on the vehicle to avoid being blocked by surrounding objects.
The last instance occurs in automobiles and trucks with aluminum or other metal bodies. This is the reason for this article, in particular.
Which Foil to Use for GPS Signal Blocking?
There are several popular brands of foil with similar characteristics in their properties, but they all work on the same principle: to attenuate (block) or reflect line-of-sight microwave signals.
The generally accepted “fact” is that this type of foil will weaken GPS/Satellite Radio signals to a point that they cannot be reliably received by your device.
How GPS Blocking Works for Vehicles
This is where things get a little more complicated because the attenuation varies depending on the frequency and other factors. The foil may block or weaken your signal just enough to lose tracking ability, but not enough to interrupt phone calls if you have cell service in your area.
The foil also has to be wrapped and taped properly around your device for it to work as designed, which can vary from application to application depending on the environment. There is no “magic” fix-all solution that will fit every scenario.
So now that we have covered some of the “basics”, let’s get into the “facts” of this matter.
First, there are many variables involved in this process that vary from vehicle to vehicle and person to person. The foil is only one part of the equation, so please don’t view it as an all-encompassing solution.
The second fact is that there are no easy answers here. Many people have posted reviews of this foil on the internet, but the results vary greatly depending on who applies it to their vehicle.
There are some reviews where people claim that the foil was completely ineffective at blocking GPS signals. Others claimed that just enough signal came through to maintain location. This is because there are several variables involved in this process.
The variables are:
1. The frequency of the device’s transmitter(s).
2. The sensitivity of your receiver(s) in your device(s).
3. The amount and angle of the foil installed on your vehicle.
4. The line-of-sight signal strength received by your device(s).
5. The line-of-sight obstructions around your device(s).
6. The materials used in the construction of your device(s).
7. Your distance from the closest cell tower or GPS satellite.
8. The number and type of devices you have installed in your vehicle at any given time.
9. Your driving habits (hard braking, hard acceleration, high speeds).
10. The construction of your vehicle (aluminum/steel body panels).
Except for number 7 above, all of these variables can vary for each device that you have installed in your vehicle at any given time. For this reason alone, it becomes virtually impossible to guarantee the results you will achieve, if any.
So here is what we recommend:
1. You must perform your test before using this foil to prove whether it works or not in your particular situation. Many drivers have driven with GPS devices for years without ever having a problem locating their vehicles, so you must prove to yourself that this foil is the solution.
2. Do not use a cell phone while testing your GPS, because it will defeat the test and skew your results since they both use the same frequencies. Use only one device at a time during your tests.
3. You must perform these tests in an open-air environment with a clear view of the sky. If you live in an urban area, you must get out of town to perform these tests. Parking garages and parking structures with concrete walls will also cause reflection problems.
4. Do not park your vehicle near a large metal object during your test(s).
5. You should test all devices at the same time to avoid a prolonged test.
6. If your device(s) does not work after installing this foil, you should do one of two things:
a. Remove the foil from your vehicle and try again with another brand or type of foil, or
b. Leave the foil off for a while and see if the GPS can locate your vehicle after a few days of use.
7. There is no guarantee that this foil will work for you, but it is effective in many cases where GPS tracking was never an issue before.
Additionally, you must know is that Aluminum Foil can block only the radio signals like GPS, 3G signals but does not block 4G LTE. The second thing is that it can’t block any signals coming from the satellite directly (ex; satnav system) because the signal sent by satellite is Laser.
Lasers are so much different from Radios. It can’t block any Laser signals as well as cell towers signal because those are Microwave signals, not Radio Signals.
Microwaves have a long wavelength and cannot penetrate through Aluminum foil or plastic wrap. The best way to stop them is by using a metal enclosure ( box).
Other Uses of Aluminum Foil
The following are the best ways to use Aluminum Foil as a blocking material.
1.) Wrapping your head-set with Aluminum foil can help you to prevent mind control and other Electronic attacks such as V2K, Voice of God.
2.) You must put some pieces of Aluminum foil in your laptop bag because it will prevent someone from seeing what you are doing through your laptop webcam.
3.) If you want to be hidden from the Spy eyes then wrapping yourself with Aluminum foil will hide you completely.
4.) Another good use for this material is that if someone is using any Remote Control Car or Drone then wrapping cell phones, Game console controllers, and remote controls into aluminum foil can disable them.
5.) How can I say No to another good use? Yes! You can also wrap your home’s doorknob with Aluminum foil so nobody will be able to open the door when you are in. You must do this before someone close your door without knocking on it.
6.) If you think that there is something wrong with your phone, laptop or tablet then you can use some aluminum foil to make sure that your privacy is safe.
7.) To protect the alarm system of your house wrapping all sensors into Aluminum foil will prevent anyone from opening them and stop the alarm.
8.) If you are using a Microphone device for recording audio then put some pieces of aluminum foil into the speaker and it will increase the quality of audio.
9.) Also, you can use Aluminum foil to clean up your old rusty razor blades because this material can prevent rusting. The best thing about this is that it prevents bacteria from growing on the blade’s surface and eventually avoids skin infections. It’s better than any chemical product!
10.) For your last but not least use of aluminum foil, wrap it around the batteries before you dispose of them because it can prevent acid leaks during decomposition.
So now you know ten uses for Aluminum Foil in your daily life! It’s a cheap and effective way to protect yourself from all kinds of spy cameras, cell phone listening devices ( bug detectors), and other wireless signals that might harm your privacy.
Does Aluminum Foil Block GPS Tracking? Conclusion
Whether aluminum foil will be an effective DIY GPS Signal blocker depends on the strength of the GPS signal that you want to block. The stronger the signal, the harder it will be for Aluminum Foil to work its magic.
Despite this fact, if your goal is to keep nosy neighbors or coworkers from snooping on your location, then aluminum foil can work wonders.
The one downside of using this technique is that you will have to make sure that the foil is wrapped completely around your device.
Also, remember that most smartphones are equipped with GPS technology for tracking purposes, so be mindful of this when considering whether or not to foil your phone.
All in all, if you’re only looking to turn your iPhone into a faraday cage (to protect your privacy), then turning it into an aluminum foil iPhone is your best option.