Ground Truth Notice
Please read this before using Ground Truth. You'll need to accept it to continue.
Watch where you walk
Surveys are done while walking with your phone held up. Look where you're going, not at the screen, especially near stairs, pets, furniture and other people. Stop walking before you read results.
Only test networks you're allowed to
Ground Truth measures the network your device is connected to: it pings your router, reads your cable modem's status page, runs speed tests and makes test DNS lookups. Use it only on networks you own or have permission to test. Some workplaces and public networks don't allow testing.
Measurements are estimates
Results depend on your device, its position, other traffic and interference at the moment you measured, and can be wrong or incomplete. Ground Truth helps you understand and improve your Wi-Fi and internet; it isn't a certified engineering survey and doesn't guarantee any level of service. Blank areas on a map weren't measured. A diagnosis is the most likely cause given what was measured, not a certainty, and the messages it drafts for your provider are yours to check before you send them.
Speed tests use data
Speed tests against a Mac on your network stay on your network. Speed tests over the internet use your internet data, which may count toward a data cap; the Mac monitor keeps its tests within the share of your allowance you set. Cellular tests are off unless you turn them on and stay within the data limit you set. You can turn automatic speed tests off in Settings.
Scans of your home are yours
Floor-plan scans, photos, measurements and your provider case stay on your device (and your iCloud, if you use it). They're shared only when you export or send them yourself. Exports leave out your location, but a floor plan and photos can still reveal where you live, so share them with care.