FAQ

No. Everything runs locally in your browser for privacy and speed. Geometry is only sent if you sign in and choose Save or Send to Dashboard. Load only retrieves items you previously saved to your own account.

Draw polygons, edit vertices, rename and duplicate geometries, hide and show items, select by click, lasso, or list checkboxes, union (Combine), subtract (by drawing or by pasting or uploading), dissolve, split MultiPolygons, buffer in kilometers, simplify in meters, validate and fix topology, add overlays, use local autosave drafts, and export to WKT, GeoJSON, and Shapefile.

Click Add and choose File or Paste. File supports .wkt, .geojson, .json, and .zip (zipped Shapefile). Paste supports WKT, GeoJSON Feature, GeoJSON FeatureCollection, and multi-line GeoJSON sequences. Only Polygon and MultiPolygon features are imported.

In the Geometries list (right sidebar), open a geometry row and click Edit. Drag vertices on the map, then click Save edit in the same row to commit. Only one geometry can be edited at a time.

When vertex editing is active, the editor locks other tools to prevent conflicting edits and corrupted geometry. Finish the edit by clicking Save edit on the active geometry row.

Not until you finish the edit. Click Save edit first, then export.

To avoid conflicting edit layers and accidental corruption, the editor allows only one active vertex edit session at a time. You can still select multiple geometries for operations like Combine, Buffer, Simplify, and export.

Click the name in the geometry list and type a new label. Press Enter or click outside the input to save. Press Escape to cancel.

Yes. Open the geometry row actions and choose Duplicate. A copy is added as a new item.

Yes. Use the visibility toggle in the geometry row actions to hide or show an item. Hidden geometries remain in your list and can still be exported when exporting all.

Yes. Open the geometry row actions and click Zoom.

Yes. Use the Undo and Redo buttons in the top right of the map. Shortcuts: Ctrl or Cmd + Z for Undo, and Ctrl or Cmd + Shift + Z for Redo. While vertex editing is active, Undo and Redo apply to that geometry’s edit steps. After you click Save edit, Undo and Redo apply to full operations like combine, subtract, buffer, simplify, and delete.

Press Esc, or click Exit in the on-map mode toast.

At the bottom of the right sidebar, use Save to store your current geometry set (or your selection) in your ClearSKY Cloud Library, Load to reopen a saved item, and Send to Dashboard to save and open the ClearSKY Dashboard with your AOI prefilled for ordering.

Yes, it is optional. If Autosave is enabled, the editor stores up to 3 rotating draft snapshots locally in your browser on this device. To restore, open Add, then Autosave, then pick a draft. Restoring replaces your current geometries.

Autosave is stored only in your browser storage on this device. It is not uploaded, not synced across devices, and it disappears if you clear site data or browser storage.

Autosave is suppressed while vertex editing is active to avoid saving half-finished edits. Click Save edit first, then autosave will capture the updated geometry.

Yes. Open Add, then Autosave, then uncheck Autosave locally on this device. Turning it off clears the stored drafts for this browser.

Toggle Select mode in the left toolbar. Left-click a polygon to add it to the selection. You can also draw a lasso polygon to select intersecting shapes.

In Select mode, right-click a selected polygon to remove it from the selection. Use Clear (left toolbar, Select section) to clear the full selection.

Yes. Use the checkbox next to each geometry in the right sidebar to add or remove it from the selection.

Click Select all in the left toolbar (Select section).

Click Invert in the left toolbar (Select section).

Toggle Delete mode (left toolbar) and click a polygon to remove it. For MultiPolygons, clicking removes the part you clicked. If there is only one part, the entire geometry is removed.

Select 2 or more shapes, then click Combine (union). The result becomes one geometry.

Select one or more geometries, then click Dissolve. Dissolve merges adjacent or overlapping parts and can help remove internal boundaries that are not meaningful for your AOI.

Combine merges multiple selected geometries into one geometry. Dissolve focuses on merging parts and internal boundaries, especially for MultiPolygons or geometries with complex internal structure. Use Combine to merge separate items. Use Dissolve to clean up a multiparts style geometry.

Select one or more shapes, toggle Subtract by draw, then sketch the area to cut away. The drawn polygon is subtracted from the current selection.

Select shapes, click Subtract, then paste WKT or GeoJSON, or upload a zipped Shapefile (.zip). The polygons are applied sequentially to subtract from your selection.

Select a MultiPolygon, then click Split. Each part becomes its own Polygon in the list.

Select shapes, click Buffer, then enter a distance in kilometers. The buffer result replaces the original shapes in the selection. You can undo if needed.

Round creates a normal distance buffer around the shape. BBox expands the geometry’s axis-aligned bounding box by the given distance and keeps 90 degree corners.

The slider is capped for convenience, but the number input accepts larger values. This is useful for large AOIs or large clearance distances.

Select shapes, click Simplify, then enter a tolerance in meters. High quality mode uses a Douglas-Peucker style simplification. You can undo if you over-simplify.

Select the geometry and use the Strip holes tool. This removes interior rings and keeps only the outer boundary.

Select the geometry and use Extract holes. The holes are converted into new polygon geometries so you can keep, edit, export, or delete them separately.

WKT, GeoJSON (.geojson or .json), GeoJSON sequences (multi-line JSON objects), and zipped ESRI Shapefile (.zip). The editor imports Polygon and MultiPolygon features. Non-polygon geometry types are skipped.

WKT (as a GEOMETRYCOLLECTION), GeoJSON (FeatureCollection), and ESRI Shapefile (.zip). You can export all shapes or only your selection.

Toggle Export selection only (footer of the right sidebar). Then click Download for WKT, GeoJSON, or Shapefile.

Yes. Shapefile exports include a simple attribute called label for each feature when available. Add more attributes later in a GIS if needed.

GeoJSON and Shapefile exports include a label property per feature when available. WKT export is geometry-only.

Often yes. On GeoJSON and Shapefile import, the editor tries to use properties like label, name, NAME, title, or id as the geometry label. Duplicate names are auto-numbered within the same import.

Yes. You can paste multiple GeoJSON objects separated by new lines. Polygon and MultiPolygon entries are imported.

Yes. Use Copy under WKT or GeoJSON in the Export section, or Copy in the geometry row actions.

The editor assumes WGS84 (EPSG:4326) longitude and latitude for input and output. If your Shapefile uses a different CRS, reproject it to EPSG:4326 before importing. Buffer distances are in kilometers.

Polygon and MultiPolygon. Points and lines are skipped on import and are not exported.

All Polygon and MultiPolygon features are imported as individual items in the list.

The main editor does not import or export WKB directly. Use the free converters (WKT to WKB, GeoJSON to WKB, WKB to GeoJSON) at polygon.clearsky.vision. They run entirely in your browser and are designed for PostGIS and other spatial databases.

WKT and GeoJSON can describe many features, but a single WKB value represents one geometry (Point, Polygon, Multi*, or GeometryCollection). The WKB tools combine multiple WKT or GeoJSON geometries into one Multi* or GeometryCollection WKB, and decode that back into a single Multi* or GeometryCollection geometry.

When adding geometry, the validation modal reports common issues like unclosed rings, self-intersections, holes, and duplicates. You can apply fixes before proceeding, or proceed anyway.

Use Fix self-intersections in the validation modal, then proceed. This applies a geometry clean-up step to repair invalid intersections when possible.

Use Remove interior rings in the validation modal. This removes holes and keeps only the outer boundary. If you want holes as separate polygons, use Extract holes in the editor tools after importing.

Duplicates are identical rings or parts repeated in a geometry. Removing them prevents invalid topology and reduces the chance of failures in operations like union, buffer, and export.

Closed rings are required for valid Polygons and MultiPolygons. Non-closed rings can cause errors in operations and exports.

Proceed anyway imports the geometry as-is, even if validation reports issues. Some operations may fail or produce unexpected results until you fix topology.

If the subtraction geometry fully covers a selected shape, the result is empty and the shape is removed. Use Undo to restore, or subtract a smaller area.

Open Overlay, enter a tile URL like https://server/{z}/{x}/{y}.png, then click Add tiles.

Yes. Open Overlay, choose a .geojson or .json file, then click Add GeoJSON.

Yes. Open Overlay, choose a .tif or .tiff. EPSG:4326 or EPSG:3857 works best. Very large rasters can be slow to render in the browser.

Use the Opacity slider in the Overlays controls.

Click Clear in the Overlays section.

The basemap shows attribution (OpenStreetMap and Carto). If you add custom tiles, follow the provider’s attribution rules.

No. Editing and exporting work without an account. A ClearSKY login is only needed for Save, Load, or Send to Dashboard.

We store the geometry you choose (all or selection) as GeoJSON in your Cloud Library along with the name you provide. We do not store your basemap, overlays, or any unrelated data.

The geometry is saved to your account (like Save) and the ClearSKY Dashboard opens with your AOI prefilled so you can configure and submit an order.

Use Load to open your Cloud Library. You can delete items there. Orders already created in the Dashboard keep their own copies.

We do not log anonymous editing actions. When you sign in and use Save, Load, or Send, we store standard account metadata and the saved item so those features work. Otherwise, your work remains in your browser.

Yes. The app runs in your browser and does not upload geometry unless you explicitly choose Save or Send to Dashboard. Loading retrieves only your own saved items.

No tracking for anonymous use. Authentication sets session cookies only if you log in to use Save, Load, or Send.

Once the page is loaded, many actions keep working offline. Refreshing the page clears in-memory work, so export before you refresh.

Latest Chrome, Edge, Firefox, and Safari are recommended. Mobile works, but desktop offers a better editing experience.

Use Simplify to reduce vertices, split very large AOIs into smaller pieces, hide overlays, or work in smaller batches. Undo lets you experiment safely.

Buffers are computed in kilometers while working in WGS84 longitude and latitude. For legal or survey-grade precision, validate results in a GIS using an appropriate projected CRS.

Limits depend on your browser memory. Extremely large files can be slow or fail to parse. Split or simplify before importing.

Your exported geometry is yours. Basemap and overlay tiles may have their own licenses. Check your provider.

Make sure the input is valid WKT or valid GeoJSON (Feature, FeatureCollection, or multi-line GeoJSON objects) and that it contains Polygon or MultiPolygon geometries.

Fix topology first in the validation modal. Self-intersections, duplicate rings, and other invalid polygons can cause union operations to fail or produce unexpected results.

Buffers are computed on longitude and latitude coordinates, which introduces distortion at extreme latitudes and large distances. Use smaller buffers or verify results in a projected GIS.

Some browsers block clipboard access. Download the result as a file instead, or enable clipboard permissions for this site.

Maybe. If Autosave was enabled, open Add, then Autosave, then restore the latest local draft (this replaces your current geometries). If autosave was off (or you cleared site data), recovery is not possible.

Open /feedback and describe what you were doing, which tool you used, your browser, and if possible include a small WKT or GeoJSON example so we can reproduce the issue.