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Shelly keeps going offline or won't connect to Wi-Fi (incl. FRITZ!Box): settings that actually help

Shelly Device: Gen2/Plus, Gen3 and Gen4 (Wi-Fi devices); the principles also apply to Gen1 · Updated · Auch auf Deutsch

Firmware as of: As of 26 Oct 2026 per the official Gen2+ changelog: stable 2.1.1, 2.0.3 or 1.7.6 depending on the device. WPA3 since 1.4.0; since 1.7.5 "Secure provisioning" automatically turns off the open access point and BLE RPC after setup.

Generations: Gen1, Gen2/Plus, Gen3, Gen4

What you see: The device keeps showing offline or "pending connection" in the Shelly app, or can't be added to Wi-Fi at all. Often it affects only some devices, and often it starts after a router change, a router update, or switching on WPA3 or mesh.

What it means: Shelly devices are small 2.4 GHz radio modules, often behind switches, in wall boxes or in distribution boards. They're more sensitive to weak signal and to modern router features than phones and laptops. Shelly's official Network Design Guide lists the settings that matter.

Cost: €0 / CHF 0 for steps 1–5. An extra access point or repeater costs money, but is only needed if the signal at the installation spot is too weak.

Step 1: Is the device reachable locally? 2 min

  1. Look up the device's IP address in your router (FRITZ!Box: Home Network › Network).
  2. Open http://<IP address> in a browser on the same Wi-Fi.
  • Web interface loads: the device is on Wi-Fi. Continue with step 2 (cloud) and step 3 (signal).
  • Doesn't load: the device is not on Wi-Fi. Continue with steps 3 and 4.

Step 2: Check the cloud connection 2 min

In the web interface under Settings › Cloud, check that the cloud is enabled and connected. shelly.guide names this as the fix when a device works locally but shows "pending connection" in the app. At control.shelly.cloud you can also see whether the device is online in your cloud account.

Step 3: Check signal strength 5 min

Read the Wi-Fi status (RSSI in dBm) in the web interface.

  • Official guideline: at least −67 dBm and at least 25 dB signal-to-noise ratio.
  • The German-language Shelly forum's rule of thumb: the closer to 0, the better; values around −80 dBm are barely usable.
  • If the device sits in a metal enclosure or distribution board, often only an access point or repeater closer to the device helps.

Step 4: Configure the router correctly 15 min

According to the official Shelly Network Design Guide (Gen2+):

  • 2.4 GHz, 20 MHz channel width, channel 1, 6 or 11, fixed rather than automatic.
  • WPA2 (AES/CCMP). A WPA3 transition mode with PMF "required" can lock devices out. (WPA3 is supported since firmware 1.4.0 according to the changelog.)
  • No band steering and no 802.11r (fast roaming) for the network the Shelly devices use.
  • Don't set the minimum data rate above 12 Mbit/s, and no more than about 35 devices per access point radio.
  • A fixed IP address via DHCP reservation in the router instead of a static IP on the device.

FRITZ!Box (menu names per recommendations in the German-language Shelly forum; they can differ slightly by FRITZ!OS version and interface language):

  1. Wi-Fi › Radio Channel: adjust the radio channel settings, choose a fixed channel 1, 6 or 11 in the 2.4 GHz band; turn Wi-Fi steering / band steering off for the test.
  2. Wi-Fi › Security: encryption WPA2 (CCMP) instead of "WPA3" or "WPA2 + WPA3"; turn off the option for protected management frames (PMF) if devices won't connect.
  3. Wi-Fi › Security › further security settings: enable the option that lets active Wi-Fi devices communicate with each other (important for local control and integrations).
  4. Do not put Shelly devices on the guest network.
  5. For the fixed IP address: in the FRITZ!Box under Home Network › Network, enable the option to always assign the same IPv4 address for the device (a FRITZ!Box function; exact name varies by FRITZ!OS).

Note on mesh and multiple access points: the forum describes dropouts when devices hop between several access points with the same network name. A test with just one access point shows whether that's the cause.

Step 5: Eco mode and power supply 5 min

  • A shop's troubleshooting help page names Eco mode as a possible cause of dropouts. Turn it off for the test (settings in the web interface).
  • For low-voltage devices (e.g. 12/24 V), the same source names a weak or unstable power supply as a cause. Swapping a low-voltage power supply is unproblematic; anything on 230 V is a job for an electrician.

Step 6: Reset the network and add the device again 15 min

Only once the router is right:

  1. Reset only the network settings, not everything. shelly.guide advises trying this before a factory reset.
  2. From firmware 1.7.5, the device's open access point is turned off after setup ("Secure provisioning", per the changelog). After a network or factory reset the device can be set up again.
  3. Add the device again in the Shelly app, or connect to the device's own Wi-Fi and open http://192.168.33.1 (per shelly.guide), then enter your 2.4 GHz network.
  4. If automatic adding doesn't work, Shelly support describes an update and manually adding the device in Shelly Smart Control.

How to trigger the reset for your model is in the official reset guide. For permanently installed devices, don't remove covers of 230 V installations to reach a button; call an electrician for that.

When to contact support

  • The device loses its connection even with a good signal (better than −67 dBm) and the router settings from step 4.
  • The device keeps rebooting, gets hot or doesn't respond locally at all.
  • The device can't be set up again after a reset.

Shelly support (official). For warranty cases also contact the retailer.

Sources

FAQ

Do Shelly devices work on 5 GHz Wi-Fi?

The official Shelly Network Design Guide for Gen2+ devices assumes 2.4 GHz. The 5 GHz band can stay on at the router; what matters is that the 2.4 GHz network is configured cleanly.

What signal is good enough?

The official Network Design Guide recommends at least −67 dBm (RSSI) and a signal-to-noise ratio of at least 25 dB. Values like −75 dBm or worse are a typical reason for dropouts.

Is the device broken if it's offline but still switches on the home network?

Usually not. If the device is reachable locally by its IP address but offline in the app, the problem is often the cloud connection. shelly.guide describes the Settings › Cloud switch in the web interface for this.

Do I have to factory reset first?

No. shelly.guide advises resetting only the network settings first and considering a factory reset only afterwards.

More Shelly guides

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