Wi-Fi signal level, also known as Received Signal Strength Indicator (RSSI), is a measure of how well your device can receive the wireless signal from the router or access point. It is usually expressed in decibel-milliwatts (dBm), which is a logarithmic scale that ranges from -30 dBm (very strong signal) to -100 dBm (very weak signal). The higher the negative value, the weaker the signal.
According to the Apple Device Support Reference Materials1, iPhone and iPad will search for a stronger Wi-Fi network when the signal level drops below -80 dBm. This is because a weak signal can affect the performance, reliability, and security of your Wi-Fi connection. A weak signal can also drain your device's battery faster, as it requires more power to maintain the connection.
To check the Wi-Fi signal level on your iPhone or iPad, you can use the following steps23:
* Open the Settings app on your device.
* Go to Wi-Fi.
* Under the Wi-Fi network list, locate the name of the Wi-Fi network or wireless router you want to check the signal strength for.
* Tap the information icon (i) next to the network name.
* Look for the RSSI value, which shows the signal level in dBm.
Alternatively, you can also use third-party apps that can display the Wi-Fi signal level on your device, such as Wi-Fi Sweetspots or Network Analyzer.
References:
* Recommended settings for Wi-Fi routers and access points.
* How to View Wi-Fi Networks Signal Strength on iPhone or iPad.
* How to View Wi-Fi Networks Signal Strength on iPhone or iPad | Guide.