Does GPS Work Without a SIM Card or Internet?

GPS is a one-way signal

GPS satellites broadcast signals that any receiver can pick up for free, with no data connection required. Your phone's GPS chip listens to these signals and calculates position and speed locally — no internet needed once it has a fix.

So why does my phone want an internet connection?

Many phones use A-GPS (Assisted GPS), which downloads satellite almanac data over the internet to get your first fix faster. Without that assist, acquiring the initial fix can take longer — sometimes a minute or more in a cold start — but it will still work.

Practical tips for offline use

• Open the app once while online so maps or app assets are cached if needed
• Go outside with a clear sky view for the fastest fix
• Give it time — a cold start without network assistance can take longer
• Keep location permission enabled even in airplane mode (GPS still works; airplane mode only disables radios, though some phones also disable GPS unless you re-enable it manually)

The bottom line

You do not need a SIM card or data plan for GPS speed to work. You do need the app loaded at least once and, ideally, a clear view of the sky.