Polygon Overlap Checker
Detect polygon pairs that overlap and export their shared areas with source indexes for focused topology review and cleanup.
Input
This reports positive-area overlaps but does not modify source boundaries or treat shared edges as overlap errors.
Review these warnings
GeoJSON
Map preview
Understanding Polygon Overlap Checker
Validity, topology and data quality
Detect polygon pairs that overlap and export their shared areas with source indexes for focused topology review and cleanup.
Polygon Overlap Checker 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
This reports positive-area overlaps but does not modify source boundaries or treat shared edges as overlap errors.
After Polygon Overlap Checker, compare changed feature counts, coordinates and shapes with the source. Automated cleaning can resolve a technical defect while introducing an unwanted geographic change.