An interactive map of free public NTRIP mountpoints and RTK correction networks worldwide. Filter by network and access tier (free, registration, conditions); see coverage at hobbyist accuracy bands; copy server, port, and mountpoint settings into your NTRIP client. Sources include rtk2go, Centipede, EarthScope NOTA, SAPOS, ERGNSS, AUSCORS, RBMC-IP, RAMSAC, TrigNet, and dozens more — about 5,400 stations across 66 networks. For hobbyists and small shops who need centimetre-accurate GNSS without a paid subscription.
Common questions about finding and using free NTRIP RTK correction streams.
Whether you're recording where a fossil came from, marking individual rare plants for return visits, or building a garden robot — ±1 m GPS isn't enough but free network RTK gets you to centimetres. This map shows the reference stations that make that possible: connect to one within ~30 km of where you're working and your GPS goes from metres-accurate to centimetres.
You need a dedicated dual-frequency (L1+L2) GNSS receiver — almost all phones and consumer GPS devices can't do RTK in real-time, and purpose-built units start around €275.
For free network RTK, ready-to-use kits start around €449 / $490. DIY tinkerer kits from ~€275. You don't need the €2,900+ standalone category unless you work somewhere with no mobile signal.
Hobbyists, citizen scientists, makers, and small volunteer groups whose work needs cm-level positioning but doesn't justify a paid surveyor or commercial correction subscription. If your project sits between 'metre-level GPS is fine' and 'we need legal survey acceptance', this map exists for you.
Open your NTRIP client's 'correction input' or 'NTRIP' settings, paste the values from the station popup, and press Connect.
Some networks (Centipede, rtk2go) publish a special mountpoint called NEAR. Connect to it and the caster automatically sends corrections from whichever base is closest to you.
Once you're connected to a correction stream within range, multipath — signals bouncing off nearby surfaces before reaching the antenna — sets the limit on your fix quality. Placement matters more than receiver price: a $3,000 unit in a bad spot performs worse than a $300 unit in a good one.
Once your client connects, an RTK fix should appear within 30–90 seconds on a cold start, faster on a warm restart. Once fixed, your numbers should look like the ones below — anything substantially worse is a sign something is wrong, not a sign your receiver is bad.
A VRS network synthesises a virtual reference station at your location, using real stations around you. One connection point, uniform cm-accuracy anywhere inside the coverage.
Your receiver tracks signals on two radio frequency bands. Using both lets it measure and remove ionospheric delay — the main error that grows with distance — extending reliable RTK from ~10 km out to ~30 km.
A mountpoint is the name of the specific station you're connecting to — it's what you type into the 'Mountpoint', 'Stream', or 'Base name' field in your app.
All stations on this map are free. The tier labels tell you what paperwork you need first.
Three things cause this, in order of frequency: the base went offline, the station is stale (3–7 days down) and excluded from coverage, or the network changed host/port. The map is the fastest way to triage.
Float means your receiver is using corrections but hasn't yet locked the integer wavelength counts that carrier-phase RTK depends on (the 'ambiguities'). Accuracy is ~decimetre, not centimetre. Common causes: baseline too long, poor sky view, weak correction stream.
RTCM 2.x is the 1990s-era correction message format. Many modern receivers — including consumer-grade F9P boards — no longer decode it reliably. We flag these streams so you don't waste an afternoon debugging.
Yes, occasionally. The receiver can show 'RTK Fixed' with cm precision while the actual position is offset by ~19 cm or a small multiple of it — the carrier-phase ambiguity resolved on the wrong integer. There is no LED, alarm, or status flag for it.
Cm-precise but ~1 m off vs your map is normal — your fix is in the network's datum and epoch and your map is in another. The receiver isn't broken.
NTRIP runs on whatever TCP port the caster picks — usually 2101, but the value in the popup is what counts. Corporate WiFi, campus networks, and public hotspots commonly block non-web ports outright.
Solar geomagnetic storms collapse RTK fix reliability without changing anything on the ground. If your setup worked yesterday and breaks today with no other change, check the Kp index at swpc.noaa.gov before suspecting hardware.
Several regions experience persistent civilian GNSS jamming and spoofing as of 2026. If your fix loss clusters by time of day or follows airspace events, the cause is regional interference — not the base, not your hardware.
Yes. A second RTK receiver at a fixed surveyed point broadcasts corrections through a free caster; your rover connects to it like any other station on this map.
Yes — the URL updates as you pan, zoom, or select a pin. Copy the address bar to share a view; the recipient opens it and lands on the same centre, zoom and selected mountpoint.
One-minute orientation: what this map shows, how to use a station.