How to do a Wi-Fi site survey

Acutis · plain-English network help · updated June 2026

What a Wi-Fi site survey actually is

A Wi-Fi site survey is simply walking through your space with an analyzer app and measuring how strong the signal is in every room, which channels are crowded, and where coverage drops off. You end up with a rough map of your home or office that shows the good zones, the weak zones, and the dead spots. Once you can see the signal instead of guessing, fixing it becomes obvious: move the router, change a channel, or add an access point exactly where the map says you need one.

You do not need expensive gear to do a useful survey. A free app on your phone and ten minutes of walking around will tell you most of what you need to know. Larger spaces and pro installs use dedicated heat-mapping kit, but the method is the same.

Why placement beats power

The most common mistake is reaching for a "more powerful" router or a signal booster first. Wi-Fi is radio, and radio is shaped far more by where the antenna sits than by how loud it shouts. A router buried in a closet behind a TV will lose to a modest router sitting out in the open in the middle of the home every time. Power can not punch a clean signal through concrete, metal, or three rooms of furniture — but good placement routes around those obstacles. That is why a survey is worth doing before you spend a cent: it tells you whether you have a placement problem (free to fix) or a genuine coverage problem (needs another AP).

Walk the space with an analyzer app

Install a Wi-Fi analyzer on your phone, then walk slowly through every room while watching three numbers:

• Signal strength (RSSI / dBm). This is how strong your network reads at that spot. It is a negative number: closer to zero is stronger. Roughly, -50 dBm is excellent, -67 dBm is solid for video and calls, -75 dBm is shaky, and below -80 dBm is effectively a dead spot.
• Noise and channel congestion. A good analyzer shows every nearby network and which channel it sits on. If a dozen networks are stacked on the same channel as yours, your signal can be strong and still feel slow because the airwaves are jammed.
• Channels in use. On 2.4GHz, the only non-overlapping channels are 1, 6, and 11. On 5GHz there are far more, so it is usually cleaner. The analyzer's graph makes it easy to spot a quiet channel to move to.

Stand in each room for a few seconds, jot down the signal reading, and note anywhere the number falls off a cliff. Walk both bands if you can — 2.4GHz reaches farther but is slower and noisier; 5GHz is faster but fades quickly through walls.

Find dead spots and channel overlap

Two problems show up on almost every survey:

• Dead spots. Rooms where the signal drops below usable — far corners, upstairs bedrooms, the garage, anywhere behind a thick wall. Mark these on your map; they are where an access point or a better-placed router needs to reach.
• Channel overlap. If your network shares a crowded channel with neighbors, devices spend time waiting their turn to talk. Spotting a clear channel and switching to it is often a free, instant speed boost. See our guide on how to choose a Wi-Fi channel for the details.

Where to put the router and access points

With your map in hand, the fixes get specific:

• Move the router to a central, open spot, up off the floor — not in a cabinet, drawer, or media console. Re-walk the survey afterward; a short move often turns a one-bar room into three or four bars.
• If one router can not cover the whole space, add an access point or mesh node positioned between the router and the dead spot — somewhere that still reads a strong signal itself. Wire it back with Ethernet if you possibly can; a wired backhaul is dramatically more reliable than a wireless one.
• Aim for overlap, not gaps. Each AP should hand off to the next while the signal is still healthy, so devices never drop into a dead zone as you move around.

Confirm with a speed and ping test

A survey shows signal, but signal is not the same as a working connection. Once you have moved things, prove the fix in the rooms that were weakest. Run a quick browser speed test to confirm real throughput, and a ping test to check latency and packet loss for calls and gaming. If speed and ping are now solid in the spots that used to fail, the survey did its job. If signal looks strong but speeds are still poor, the bottleneck is elsewhere — your device, your router, or your internet plan — not coverage.