About WifiMapper

WifiMapper is a crowdsourced WiFi coverage mapping tool: a companion Android app captures what WiFi networks are visible as you walk around, and this website turns those captures into a searchable table and a map you can use to see where a network is actually reachable.

How it works

1. Capture. Install the WifiMapper Android app and press Start. While it's running, it periodically records your GPS location together with every WiFi network your phone can currently see - SSID, signal strength, security type and so on - and stores those readings on your phone.
2. Upload. When you're ready, the app uploads everything it has captured to your WifiMapper account here on the website. Uploaded data is stored under your account, and only you (or an administrator) can see it.
3. Explore. The WiFi Samples page lists every reading as a filterable table, and the Map page plots them on a map - every point you walked past as a blue dot, and a chosen network's own readings as red circles sized by signal strength, so you can estimate roughly where its access point sits.

Don't want to use the website?

Uploading is optional. The app has its own View Map button that draws the exact same kind of map - blue dots for everywhere you've walked, red dots sized by signal strength once you pick a network - entirely from the readings already stored on your phone. No upload, no account and no internet connection needed; it's a quick way to check coverage on the spot before you decide whether to upload anything at all.

Why walk around instead of just standing still?

A single reading only tells you a network was visible from one spot. Capturing readings continuously as you move builds up a trail of where a network can and can't be reached, and the signal-strength readings from several nearby points let you narrow down roughly where its access point actually is - useful for auditing your own coverage, spotting dead zones, or just satisfying curiosity about what's nearby.