Duplicate Feature Finder
Find exact duplicate GeoJSON features using stable geometry and property comparison, with optional ID-independent matching.
Input
Near-duplicates and geometries that are topologically equal but encoded differently are not treated as exact duplicates.
Review these warnings
Validation report
Map preview
Understanding Duplicate Feature Finder
Validity, topology and data quality
Find exact duplicate GeoJSON features using stable geometry and property comparison, with optional ID-independent matching.
Duplicate Feature Finder checks or changes structural properties of spatial data. Geometric validity concerns rules such as ring closure and self-intersection; factual accuracy requires separate real-world verification.
How to review a repair
Near-duplicates and geometries that are topologically equal but encoded differently are not treated as exact duplicates.
After Duplicate Feature Finder, compare changed feature counts, coordinates and shapes with the source. Automated cleaning can resolve a technical defect while introducing an unwanted geographic change.