Wi-Fi Scan Report Interpreter

How this reads your output

Signal, channel, band and link rates are read from the report. Windows reports signal as a percentage rather than in dBm, so it is converted using the roughly linear mapping between -100 and -50 dBm that drivers use to produce it in the first place. Where a noise figure is present, the signal-to-noise ratio is computed, which predicts throughput far better than signal strength alone.

What the results mean

Signal strength in dBm

A logarithmic scale where each 3 dB is half the power. Above -60 is good, -70 is usable, and below -80 is unusable regardless of what the router can do.

Signal to noise ratio

Signal above the noise floor. Below 15 dB, throughput collapses even with a strong signal, which is why a busy environment performs worse than a quiet one at the same strength.

Link rate

The negotiated rate, not achievable throughput. Real throughput is typically half of it at best, because airtime is shared and every transmission has overhead.

Common problems and fixes

Strong signal but slow speeds

Look at the channel and the noise floor. Wi-Fi is a shared medium, so a strong signal on a congested channel performs worse than a moderate signal on a quiet one. On 2.4 GHz, only channels 1, 6 and 11 avoid overlapping, and anything else interferes with two channels at once. Moving to 5 GHz solves it outright where the devices support it.

One device slows the whole network

This is airtime fairness, and it is inherent to how Wi-Fi works. A device on a weak signal transmits at a low rate, so it occupies the channel far longer to send the same data, and everyone else waits. Improving coverage for the worst device helps everyone more than upgrading the router does.

Frequently asked questions

More in Connection

• Connection Stability MonitorWatch a connection over time and catch the stalls a speed test never sees.
• Network Problem Finder (guided)A few questions that narrow a network problem to the layer it is actually on.