WiFi is one of many technologies we use on a daily basis. Whether it be checking email, posting to Instagram, or streaming Netflix, WiFi is a technology we rely on to stay connected. Rarely do we give it a thought until something isn’t working. Sometimes our signal is just too weak for a reliable connection. This raises the question, how far does WiFi reach?
WiFi has a effective reach of about 150 feet in an unobstructed environment. This is really the best case scenario, and assumes no obstructions at all. Walls and other obstructions can reduce your range significantly. Some materials such as concrete will almost entirely block a WiFi signal, even at very short distances. Other materials such as wood and drywall will also reduce your range, but not as much as a denser material such as brick or concrete.
Factors That Impact WiFi Reach
There are many factors involved that will effect the range of your WiFi coverage. WiFi rarely performs as expected, even professional RF engineers struggle to predict coverage areas. Here is a list of the top 5 factors that impact how far your WiFi will reach.
- Obstructions between your device and the wireless access point.
- The type and quality of the antennas both on your device and the access point.
- The frequency band being used, 2.4 GHz has a longer range than 5 GHz.
- Interference from other wireless devices.
- The firmware on your WiFi hardware.
The amount of obstructions between your device and the wireless access point is by far the most important factor in determining how far your WiFi signal will reach. WiFi signal loss is referred to as attenuation. WiFi attenuation is primarily a function of distance and obstruction. Different materials have different amounts of attenuation.
Generally dense materials such as brick, concrete, and stone have the greatest effect on your signal. In many cases a single concrete wall can completely block a WiFi signal just a few feet away. If you need WiFi coverage in these situations you will likely need an access point on both sides of the wall. Brick is also particularly hard on WiFi signals, as is most other hard dense materials.
Other materials such as wood and drywall play more friendly with WiFi. That said ,they still attenuate the signal to a certain extent. If you have more than 2 walls between your device and the wireless access point your signal may be negatively impacted. Floors tend to be a little toucher for WiFi to pass through than walls. Ideally you never want to connect between more than one floor, as this can have a significant impact on performance and stability.
Obstructions such as trees and tree branches can have a major effect on how far WiFi will reach outdoors. If you are outdoors and trying to connect to WiFi, the first thing you will want to do is to position your device to have as much of a line of sight to the access point as possible. This will increase your range greatly, possibly even double it in some cases.
The type of antenna on both the client device and the access point is an important factor. Most access points and WiFI devices come with omnidirectional antennas. This allows for easier placement since the signal is transmitted equally in all directions. This is great in most cases but does not offer the greatest range.
In some environments especially outdoors, a directional antenna can be a better choice because it helps to focus the signal in the direction it is needed rather than spraying signal every which way. Some wireless access points offer the option of using an external antenna. This can be useful in some situations where the placement of the access point is such that all client devices are facing in one direction.
It is also possible to use a high gain directional antenna on the client side. If you are using a laptop, one option is a high gain directional USB WiFi adapter. This will allow you to point the antenna at the wireless access point, greatly increasing the effective signal strength. If you often need to connect to WiFi at longer distances, investing in a directional antenna for your laptop could make sense. This works especially well outdoors in areas such as parks and campgrounds that offer WiFi.
Most modern WiFi devices are capable of operating in both the 2.4 GHz and 5 GHz frequency bands. As with most things in life, there are pros and cons to both frequency bands. Fortunately most devices are able to select the optimal choice automatically.
The 2.4 GHz band offers longer range than the 5 GHz band. This is due to the way RF signals behave. Generally 2.4 GHz offers about 40% more range outdoors, without obstructions. Indoors with walls and other obstacles the difference is even more pronounced. The lower frequency band of the 2.4 GHz band has an easier time penetrating through objects including walls, floors, and ceilings.
Of course this is not to say that everyone should stop using the 5 GHz band. In fact quite the opposite is true. The 5 GHz band is almost always better if you can use it. The amount of frequency spectrum available in the 5 GHz spectrum is so much greater, and therefore allows for much faster speeds. If you have a choice using 5 GHz is generally better.
There are some situations where you will not be able to use 5 GHz. This will include situations where you are far from the access point or have multiple obstructions in the way. In these cases 2.4 GHz is useful for keeping you connected, albeit at reduced speeds.
Fortunately most modern WiFi devices make the selection automatically. However, if you are having trouble connecting, you may want to try manually setting the frequency band on your device.
The wireless spectrum is a very busy place. Devices are assigned operating frequencies which are regulated by a government authority in most countries. In the United States we have the Federal Communications Commission (FCC). They regulate the use of the RF spectrum by frequency band and by transmit power. Many frequency bands are licensed to particular companies for specific uses. For example T-Mobile uses part of the 600 MHz band to deliver LTE and 5G data services.
Other frequency bands are licensed for a certain application such as 72 MHz for RC model aircraft operations. This regulation generally means less interference on these frequency bands.
Other frequency bands are less regulated. For example, frequency bands such as 27 MHz and 49 MHz are unlicensed bands. This allows for general use with fewer restrictions. This also means that interference is much more likely.
WiFi operates in two unlicensed frequency bands. The unlicensed nature of these frequency bands make interference all too common of an issue. Interference can come from a variety of sources, including Bluetooth devices, cordless telephones, alarm systems, baby monitors, and microwave ovens.
Interference can also come from other WiFi networks that are operating on the same channel or overlapping channels. In the 2.4 GHz band there are only 3 non overlapping channels. This makes frequency congestion a real issue, especially in dense environments such as apartment complexes and stadiums. In general 2.4 GHz band should be avoided when ever possible.
The 5 GHz band is more forgiving for a few reasons. The primary reason 5 GHz has less interference is because there are more non-overlapping WiFi channels available in 5 GHz band. Other reasons include less devices using the 5 GHz band, and the shorter range of the signal. That is right, the shorter range can actually be an advantage in dense environments.
The firmware on your wireless hardware is also a factor. Firmware can have bugs in it which can limit performance in several ways. The firmware on a wireless access point also in part determines its max transmit power. Sometimes a firmware change can enable a higher transmit power.
A higher transmit power can slightly increase range in some cases, but it is generally not going to make that much difference. WiFi is a 2 way communication, increasing the transmit power on the access point does nothing to help the client device transmit back to the access point. Generally the client radio is less powerful and the limitation anyways. That said, in some cases particularly outdoors, a higher transmit power can be beneficial.
Actual WiFi reach is a complicated thing to predict, and WiFi was never intended to be a long range communication technology. With this knowledge you can now take steps to maximize your WiFi range, or at least understand why sometime WiFi doesn’t reach as far as you might have hoped.
Wi-Fi can certainly travel through walls. Walls will decrease your signal strength somewhat. The material of the wall plays a huge factor. Dense materials such as brick, concrete, or stone will block Wi-Fi signals much more than wood and drywall. Wi-Fi can go through walls but not without losing some signal strength.
WiFi has a effective reach of about 150 feet in an unobstructed environment. This is really the best case scenario, and assumes no obstructions at all. Walls and other obstructions can reduce your range significantly. Some materials such as concrete will almost entirely block a WiFi signal, even at very short distances.
Theoretically up to a 400 feet. However at that distance connection speeds will be very low. Recommended max distance outdoors is about 150 feet. Wi-Fi will also work better at long range if there is not interference from other Wi-Fi networks.
To extend your Wi-Fi signal to a building 400 feet away you will need to use a point to point wireless bridge. This will work like a virtual ethernet cable running between the buildings. You can then take your wireless bridge and connect a wireless access point to provide coverage to client devices.
Wi-Fi does not strictly need a line of sight. However, a line of sight will greatly improve the range of your Wi-Fi and your connection quality. If you can get a line of sight between your wireless access points and your client devices
Generally Wi-Fi extenders are not worth it. In many cases they will actually make your performance worse than without the extender. Wi-Fi extenders attempt to take a poor WI-Fi signal and rebroadcast it as a stronger signal. This rarely works as well as marketing would have you believe. Powerline adapters are generally a much better option for extending your network.