Export data and save projects

Separate GIS export from project save

EditPolygon has two different kinds of output because they serve different purposes.

Do not rely on a GeoJSON or KML export to preserve every project-only state such as layer organisation, editor settings or other application metadata.

Save an EditPolygon project

Choose Save in the top toolbar to download an .epz project. Use project saves as checkpoints before complex Processing, schema changes or major geometry edits.

Open an .epz later through the normal Open workflow. Project save is browser-local file generation; it does not require uploading the project to a server.

Use autosave as recovery, not archival storage

EditPolygon keeps browser recovery state and exposes Restore autosave under More. Autosave is useful after an accidental refresh or browser interruption, but it belongs to the current browser storage and can be cleared or become unavailable.

For important work, download an .epz checkpoint. Treat autosave as a safety net rather than the only copy.

Export geometry from the top toolbar

The top-right export controls choose the geometry scope first:

• All — export every eligible project feature covered by the export workflow.
• Selected — export the current selection.
• Visible — export the currently visible geometry according to the export model.

Then choose the GIS format and open Export. Verify the output filename, format-specific settings and feature count before downloading.

Choose the destination format based on the receiving system

Export records from the Attributes table

When the desired product is a table rather than a geometry file, open Attributes and use its record export.

A complex polygon can produce an enormous WKT cell. Plain CSV exists specifically so geometry does not make an otherwise simple data export unwieldy.

Export in a required CRS

If the receiving GIS requires projected/native coordinates rather than the normal geographic project representation, use the layer's CRS tab to set and perform a CRS-aware export.

Do not simply label longitude/latitude numbers as another CRS. Reprojection changes coordinate values; assignment changes metadata only. See Assign and reproject a CRS.

Treat precision and simplification as data changes

Coordinate rounding, truncation and simplification can permanently change the downloaded geometry. Preserve full precision unless a receiving system or explicit data product requires otherwise.

If file size or rendering performance is the reason for reducing vertices, use Processing → Simplify with a map preview so the geometric consequence is visible and measurable before export.

Temporary Processing previews are not exported

Processing preview overlays are deliberately outside the project data model. They do not appear as Layers, do not enter Undo/Redo, are not saved in .epz and are not included in export. Run the Processing operation first when the preview should become a real output layer.

Verify in the destination system

After downloading an important output, open it in the actual receiving application and check:

• Feature count and geometry family.
• Required attributes and names.
• CRS/location.
• Holes and multipart structure.
• Coordinate precision.
• Format-specific presentation such as KML styles if relevant.

A successful download only proves that the file was generated; destination verification proves it is useful for the intended workflow.