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.
