Lab Guide - Diagnose a Problem
How to tell whether the problem is Wi-Fi or your ISP
A browser test cannot conclusively prove the root cause, but a few controlled comparisons can narrow the pattern. Ethernet that is also slow points toward the WAN path, router WAN side, device, or provider. Good near-router Wi-Fi with poor room results points toward coverage or interference.
One-Sentence Answer
Compare Ethernet, near-router Wi-Fi, problem-room Wi-Fi, other devices, and another time of day before deciding where the bottleneck likely sits.
Quick Takeaways
- Ethernet also slow: investigate WAN, router WAN, device, or provider path.
- Wi-Fi good near the router but poor in one room: likely coverage or interference.
- One device performs poorly while others work: possible device limitation.
- Problems only at busy hours may be consistent with time-of-day congestion.
Step 1: Test near the router
Run Internet Health Check from the same device close to the router. If the result improves dramatically, the problem-room result may be affected by distance, walls, interference, or router placement.
Step 2: Test the problem room
Run the same test where the issue happens. Record the room label for your own notes. Large room-to-room differences are consistent with Wi-Fi coverage or interference, especially in larger homes or homes with dense construction materials.
Step 3: Add Ethernet when possible
A wired test removes most Wi-Fi variables. If Ethernet and near-router Wi-Fi are both weak, the next step is to investigate the router, device, WAN path, or provider-side service. If Ethernet is strong, focus on Wi-Fi coverage and device differences.
When to contact an ISP or technician
Contact support when repeated Ethernet tests are poor, when multiple devices fail in the same way, when the service drops completely, or when you have saved results that show a repeated pattern.
Frequently Asked Questions
Does a slow Wi-Fi test prove my ISP is slow?
No. Wi-Fi adds variables such as distance, interference, device radio quality, and router placement. Compare with near-router and Ethernet tests first.
What if Ethernet is also slow?
That pattern may involve the WAN connection, router WAN path, provider path, or the testing device. Repeat the test and contact support if it persists.
What if one room is always worse?
That is consistent with Wi-Fi coverage or interference. Router placement, an extender, or a different access point layout may help.