# Accuracy Expectations

RTK accuracy depends primarily on your distance to the nearest base station. This page sets realistic expectations so you can plan your fieldwork accordingly.

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## What to Expect

RTKdata delivers centimeter-level accuracy when you're within coverage. Check the [Coverage Map](https://rtkdata.com/coverage/) to verify your area before heading to the field. Performance depends on distance to the nearest base station, sky view, and internet stability.

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## Understanding the Coverage Map

The [RTKdata Coverage Map](https://rtkdata.com/coverage/) uses two color zones:

* **2 cm zone:** RTK FIX reliable, survey-grade accuracy
* **2–10 cm zone:** RTK FIX achievable, good for mapping and agriculture
* **Outside colored areas:** No nearby base station — accuracy depends on distance to nearest station

> **Always check the coverage map BEFORE going to the field.** Knowing your expected accuracy in advance prevents frustration and wasted time.

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## What Affects Accuracy Beyond Distance

### Sky View / GNSS Environment

* **Best:** Open field, no obstructions above 15 degrees elevation
* **Good:** Rural area with scattered trees
* **Challenging:** Near buildings, under partial tree canopy
* **Poor:** Urban canyons, dense forest, near large metal structures

Multipath interference (signals bouncing off buildings or metal) is the #1 accuracy killer after distance.

### Internet Connection

RTK requires real-time corrections. High latency degrades accuracy:

* **< 1 second latency:** Full RTK performance
* **1–3 seconds latency:** Slightly degraded, may see more FLOAT
* **> 3 seconds latency:** Corrections become stale, accuracy drops significantly

Use a stable 4G/5G connection. Avoid public Wi-Fi or VPNs.

### Atmospheric Conditions

* **Ionospheric activity** (solar storms) can degrade RTK, especially at longer baselines
* **Tropospheric conditions** (heavy rain, extreme temperature inversions) have minor effects
* These are rarely the primary cause of issues — check distance and sky view first

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## "I'm in the 2–10 cm Zone — What Does That Mean?"

If the coverage map shows you're in the **2–10 cm zone**:

* **RTK FIX** is achievable but may take longer to converge
* Horizontal positions will typically be within **2–10 cm** of true position
* Vertical accuracy will be **1.5–2x worse** than horizontal
* This is **sufficient for:** drone mapping, photogrammetry (with GCPs), agriculture guidance, general construction layout
* This is **NOT sufficient for:** survey-grade control points, precise boundary surveys, or measurements requiring < 2 cm

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## When to Consider a Local Base Station

If you regularly work in an area without nearby RTKdata coverage, hosting a local base station may be the best solution:

* **RTKdata provides the hardware** (compact GNSS station, size of a large water bottle)
* **You provide:** a location with clear sky view, power (1.5W USB-C), and Wi-Fi (2.4 GHz)
* **Benefit:** 1 year of free RTK service
* **Calibration:** 12–24 hours automatic after installation

See [Host a Base Station](https://docs.rtkdata.com/support/host-a-base-station) for full details and requirements.

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## Improving Your Results

### Quick Wins

1. **Move to open area** — Even 20 meters away from a building can make a difference
2. **Wait longer** — Give RTK 60–90 seconds to converge. Don't rush.
3. **Check your mountpoint** — Use `AUTO` (ALL CAPS). Wrong mountpoint = no corrections.
4. **Use the nearest regional server** — EU server for Europe, AUS for Australia/Oceania
5. **Stable internet** — 4G hotspot beats weak Wi-Fi every time

### For Best Possible Accuracy

1. Work within 15 km of a base station
2. Use a survey-grade or high-quality mapping receiver
3. Ensure clear sky view (15 degrees elevation minimum)
4. Use a stable 4G/5G internet connection
5. Wait for RTK FIX and verify it's stable before collecting points
6. Apply the correct geoid model for orthometric heights (see [Understanding Heights](https://docs.rtkdata.com/get-started/understanding-heights))