GPS & coordinates

Onsite can capture location coordinates automatically when you record field data - on a G1 drilling form's Record position button, for example. Configuration > GPS lets you choose where coordinates come from; Configuration > Defaults lets you choose what coordinate system they're reported in.

GPS sources

Onsite supports four ways of getting your current position:

Built-in GPS chip

Most field tablets have an integrated GPS receiver. If yours does, this is the most accurate and convenient option.

• Pros: High accuracy, works offline, no extra hardware
• Cons: Only available on devices with a GPS chip - most laptops don't have one

Windows-based (IP + Wi-Fi)

Windows can estimate your location from your IP address and nearby Wi-Fi networks. Onsite can use this estimate when no better source is available.

• Pros: Available on any Windows device
• Cons: Accuracy is very low - typically within a few kilometres, sometimes worse

Windows-based location is fine as a fallback but is not accurate enough for geotechnical fieldwork. Use a built-in GPS chip or an external receiver when precise location matters.

External Bluetooth GPS

Connect a dedicated GPS receiver to your device via Bluetooth. High-accuracy RTK or differential GPS units typically connect this way.

• Pros: Very high accuracy, including survey-grade
• Cons: Requires pairing and keeping the receiver charged

Manual entry

Turn off automatic capture and enter coordinates by hand - as latitude/longitude or local X/Y values.

• Pros: Works anywhere, no hardware dependency
• Cons: Slow, error-prone, depends on knowing the coordinates ahead of time

Coordinate systems

Field positions are recorded in a coordinate system appropriate to your region. Onsite uses EPSG codes to identify coordinate systems - a standard numeric catalogue covering most coordinate reference systems worldwide.

Configure your project's coordinate system in Configuration > Defaults > Local Coordinate System. Onsite converts captured GPS positions into your chosen system automatically. See Form defaults for the broader defaults configuration.

If you're not sure which EPSG code to use, check with your surveyor or project lead. Common examples:

• EPSG:4326 - WGS84 lat/long (what GPS chips natively produce)
• EPSG:28992 - Dutch RD (Rijksdriehoekscoördinaten)
• EPSG:27700 - British National Grid
• EPSG:25832 - ETRS89 / UTM zone 32N (central Europe)

Hundreds of other codes exist for regional and national coordinate systems.

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See also

• Form defaults - where the project coordinate system is set
• Camera - other per-device settings