Two wireless links are involved

When a device uses an extender, traffic often crosses a client-to-extender link and an extender-to-router link. The slower or less stable of those paths can limit real throughput. This is why testing beside the extender can still produce lower speeds than testing beside the router.

Placement can trade coverage for backhaul quality

Moving the extender farther toward a dead zone can make the extended signal stronger in that room while simultaneously weakening the extender’s connection to the router. The goal is not maximum distance; it is a balanced location with a reliable upstream signal.

Band choice matters

2.4 GHz generally travels farther and penetrates obstacles better, while 5 GHz can offer more capacity at shorter ranges. Dual-band and tri-band designs can use radios differently, and some models offer features intended to optimize the path. The best choice depends on the model, router and environment.

Interference and channel congestion

Neighbouring WiFi networks, Bluetooth devices, older clients and household electronics can reduce usable airtime. A speed problem that appears only at busy times may be congestion rather than a faulty extender.

Compare correctly

  1. Use the same client device for each test.
  2. Test the router and extender at comparable distances.
  3. Confirm which network or node the device is actually using.
  4. Repeat tests at different times instead of relying on one result.
  5. Check whether the router itself is delivering the expected internet speed.

When Ethernet can help

If your extender supports access-point mode and Ethernet is available from the router to the target area, using a wired uplink can remove the wireless backhaul bottleneck. Not every model supports AP mode, so check the exact model guide.

What to change first

Start with placement, then confirm the router link, then evaluate bands and interference. Firmware can be checked after connectivity is stable. Avoid factory-resetting a working extender simply because a speed test is lower than a direct router test. For a step-by-step diagnostic, use the slow extender speed guide.