Run this test in the problem room and again beside the router. If the nearby result is much better, Wi-Fi coverage or interference is more likely than a slow broadband line.
Run several tests at different times for a representative result.
Compare location-to-location results rather than one headline speed. Ethernet provides a useful control result because it removes the wireless part of the path.
This page uses the same browser transfer sequence as the internet speed test, but the diagnostic question is different: how does performance change across the local wireless link? Start beside the router, then repeat in the problem location on the same device. If possible, add an Ethernet control result.
A result includes both Wi-Fi and every network segment beyond it. LumaProbe cannot read signal strength, channel use or radio band from most browsers, so location and connection type must be recorded by the person running the test.
Use one device and one browser for comparisons. Pause cloud backups, game downloads, streaming and large file transfers, then note whether the device is connected by Wi-Fi, Ethernet, mobile data or a VPN. Run the check at least three times instead of choosing a single unusually good or bad result.
Change only one condition at a time. For a Wi-Fi problem, compare beside the router with the affected room. For a suspected broadband fault, add an Ethernet result if practical. Record the time because congestion and provider work can make the same connection behave differently during the day.
A large drop between the router and another room suggests coverage, interference or node placement. Similar poor results beside the router and over Ethernet point away from coverage and towards the device, router, broadband line, provider or test route. One slow device while others are healthy suggests a device-specific issue.
The advertised Wi-Fi number on a router is a shared theoretical radio rate, not an expected internet result in every room. Walls, neighbouring networks, device antennas, band selection and wireless backhaul all affect usable throughput.
A browser sees the complete path from this device to LumaProbe, including the device, local network, provider route and test server. It cannot isolate the broadband line on its own. Browser scheduling, security software, VPNs, extensions and background activity can also influence a short test.
Treat the result as diagnostic evidence, not a contractual line measurement or a live provider-outage declaration. A provider can test a different network boundary and report a different valid number. The most useful conclusion usually comes from controlled comparisons and repeated observations.
Move the router into the open and away from metal, televisions and dense obstructions. Reconnect the affected device, test both available bands when you understand the router settings and check for firmware updates from the provider or manufacturer.
Consider hardware only after the comparisons identify a coverage problem. Ethernet or a wired access point is usually the most stable solution for fixed devices. Mesh can help several weak rooms when nodes can be placed where they still receive a strong backhaul signal.
Read the complete LumaProbe test methodology and privacy notes →
No browser test is exact. Device performance, browser limits, server distance and other network traffic affect the result. Compare repeated tests under the same conditions.
Test results are stored only in your browser when local storage is available. The public application does not create a user account or central result profile.
Repeat the test, pause other traffic and compare Wi-Fi with Ethernet. Change one condition at a time so the cause becomes clearer.
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