Paste a FeatureServer or MapServer layer URL and download the whole layer as one GeoJSON FeatureCollection in WGS84. The paged download runs in your browser against the layer’s own server; where a server can’t produce GeoJSON itself, the converter measures and corrects Esri ring winding so polygons come out right side out. Free, no account, nothing uploaded.
Paste the layer URL above, the one ending in /FeatureServer/0 or /MapServer/3. The tool reads the layer's own record count and page size, downloads every page straight from that server into your browser, and hands you one .geojson FeatureCollection in WGS84 (EPSG:4326). Nothing passes through our servers and nothing is stored.
The county parcel REST atlas lists the verified layer URL for 155 counties, with searchable fields and a sample query. If your county is indexed, copy its endpoint from the atlas page and paste it here.
That is a ring-winding problem, and this tool is built to avoid it. Esri JSON winds outer rings clockwise; the GeoJSON spec (RFC 7946) requires counterclockwise. When a server cannot produce GeoJSON itself, the converter measures each ring's winding and re-orients it, so strict readers see proper polygons with holes instead of inside-out shapes.
Usually one of two things. Some GIS servers do not send CORS headers, so a browser cannot fetch them directly from another site; the data is still public, but you would need to fetch it outside the browser (curl, QGIS, a script). And some layers cap or disable querying entirely. The error shown names which call failed.
Related: the county parcel REST atlas for finding layer URLs, the radius notice tool which runs free on GeoJSON you bring, and the guides to converting ArcGIS REST to GeoJSON, getting parcel GeoJSON, and GeoJSON vs Shapefile