What Is WiFi’s Maximum Range?

What Is WiFi’s Maximum Range?

A WiFi router or access point (AP) is like any other radio transmitter/receiver—it uses radio frequencies to communicate. The difference is, of course, that WiFi radio signals only connect to WiFi-enabled devices. While an AM radio station can potentially transmit its signal across hundreds of miles, a WiFi router has a much smaller footprint. So, what is WiFi’s maximum range?

WiFi Transmission Basics

For those cutting to the chase, 2.4 GHz (viz, IEEE 802.11ax/g/n) generally extends up to 150 ft (46 m) indoors and up to 300 ft (92 m) outside. If your WLAN utilizes 5 GHz (viz, 802.11ac/ax/n) frequencies, consider yourself lucky if your AP broadcasts as far as an AP using 2.4 GHz. Note that both 802.11n/ax routers broadcast across 2.4 GHz and 5 GHz frequencies.

Why do 5 GHz frequencies have a shorter reach than 2.4 GHz bands? The higher a radio’s bandwidth frequency, the less its range. When transmitting at equal power (watts), an AM radio signal will span much farther than one from an FM station. Licensed AM radio frequencies (in the U.S.) range from 535 kHz to 1605 kHz; FM stations broadcast across frequencies from 88 MHz to 108 MHz.

While AM transmitters can reach listeners located at greater distances than FM, the amount of data transmitted is limited compared to that of FM. AM stations broadcast in monaural; FM stations broadcast in stereo. FM bandwidths can include extra data such as textual information (song title, band, time of day, etc.) using the Radio Data System (RDS) protocol; AM frequencies cannot. To compare, an AM signal uses 30 kHz of bandwidth while FM requires up to 80 kHz.

Factors other than distance affects WiFi AP range and signal strength. Consider obstructions (and their composition) and surrounding radio interference as your biggest challenges in maximizing your WLAN footprint.

The quality (power) of your AP transmitter and the type of WiFi protocol (2.4 GHz or 5 GHz) matters, too. For example, if you’re using legacy WiFi 802.11a (5 GHz), expect to achieve about 75% of this range (i.e., indoors 115 ft/35 m and outdoors 225 ft/69 m). Similar limitations apply to 802.11b.

Maximum WiFi Power by Region

WiFi power is measured by maximum allowed transmission power, or Equivalent Isotropically Radiated Power (EIRP). EIRP is expressed in milliwatts (mW) or decibels per milliwatts (dBm). Below is a table of maximum EIRP for selected world regions.

Region	Max EIRP in dBm	Max EIRP in mW	Regulatory Agency
Europe, Middle East, Africa, China, most of SE Asia	20	100	ETSI (standard)
North & South America	30	1,000	FCC, others
Japan	10	10	ARIB
France	7	5	ARCEP

Factors Affecting WiFi Maximum Range

Physical obstructions such as metal or masonry walls can reduce WiFi range by 25%. These barriers reflect most of the WiFi signal, which is great if one has a clear line-of-sight to the wireless AP but not so much if a device is behind the obstruction. Remember every wireless environment is different and your WiFi performance will vary depending upon a host of variables.

For example, a notable WiFi signal killer is chicken wire, used in older homes to build plaster walls. The gaps in the metal make the room an ideal Faraday cage, trapping all radio signals within.

Variables include:

1. WiFi signal interference. Devices emitting and receiving electromagnetic fields or EMF (microwave ovens, IoT devices) can interfere with your device’s WiFi reception. If you have lots of home wireless gizmos, ensure that your IoT gear uses 2.4 GHz. Reserve 5 GHz for UHD TVs, gaming consoles and other bandwidth hogs.

2. Wireless Router/AP placement. If you’ve located your AP in a corner of your home, you may be unable to send WiFi signals to devices on the far side. Centralizing the location of your AP will help eliminate WiFi dead zones and deliver a more powerful, uniform signal to all reaches of your residence.

3. Updating Router/AP firmware. If you have a legacy router, a firmware update may help increase data speeds and performance. Manufacturers periodically update their routers’ firmware to improve UX. Check the manufacturer’s website; you’ll usually find a link to download the latest updates.

4. Reboot Router/AP periodically. By restarting your router, you’ll expel unwanted devices piggybacking on your network (check those security settings!), reset device connections and disrupt any malign external attacks on your WLAN. Often, this simple procedure will increase your network’s range and data speeds.

Extending Your WiFi’s Maximum Range

If your WLAN’s coverage area and performance aren’t what you expect, you may need to go beyond the traditional “volcano” router once customarily used to serve the entirety of a home. See our articles on mesh networking and WiFi repeaters and extenders for details. Adding additional APs to your home WLAN will eliminate dead zones and provide a stronger WiFi signal for all your devices.

For those needing a less expensive option than meshnets, consider adding an external antenna to your laptop or PC. When surveying the models available, you’ll see many antennas labeled “high gain.” This description indicates that the antenna is “omnidirectional,” viz, it propagates signals in multiple directions. If you’re looking to extend your WiFi’s outdoor range, consider a Patch Antenna, a unidirectional antenna that hangs on a wall.

Not that we’re promoting any specific manufacturer over another, but see this antenna offering from Amazon as an example. Note that this product offers two separate antennas, one for 2.4 GHz and one for 5 GHz. Also, before installing these antennas, we recommend you review our article on PCIe cards.

If you’re looking to extend your maximum WiFi range on the cheap, take a look-see at this YouTube vid from techquickie:

Coda

To stress that obstructions are your biggest challenge to maximizing WiFi range, we adopt the following from Nashville Computer Guru, a home WiFi installer and troubleshooter.

Examples of Radio Frequency (RF) Reflective & Absorption Barriers

Barrier Type	Interference Potential
Wood	Low
Synthetics	Low
Glass	Low
Water	Medium
Bricks	Medium
Marble	Medium
Plaster	High
Concrete	High
Bulletproof Glass	High
Metal	Very High

Mirrors, paired but unused Bluetooth (BT) devices and even Christmas lights can diminish WiFi range and speed. And where you live, sadly, plays a part as well. Rural residents and city “outskirters” don’t receive the same high data speeds that urban and suburban subscribers do. Ultimately, your network performance will depend heavily on your Internet service provider.