GeoJSON Merger
Combine multiple GeoJSON files into a single FeatureCollection. Works entirely in your browser — no uploads.
About merging
This tool accepts standard GeoJSON and line‑delimited GeoJSON (NDJSON/GeoJSON Lines). Each input is normalized to a FeatureCollection and all Features are appended into one result. You can also choose which properties to keep via a simple checklist (with an “Include in all files” quick action). If any input is TopoJSON (type: Topology), please convert it to GeoJSON first using the converters page.
How to merge GeoJSON files online
- Click “Choose files” (or drag and drop) and multi‑select your .geojson or .json files.
- Review the per‑file size and feature counts; fix any parse errors if shown. Choose which properties to include (or click “Include in all files”).
- Scroll to see the combined text preview and a live map preview.
- Download the result as merged.geojson.
Tips:
- Works with FeatureCollections and single Features/geometries. Inputs are normalized into one FeatureCollection.
- Large datasets render quickly by sampling a subset for the preview map; the downloaded file always includes all features.
- After merging, you can shrink file size with the GeoJSON Minifier.
Supported formats and scope
- GeoJSON FeatureCollection, Feature, or raw Geometry objects.
- NDJSON / GeoJSON Lines (one JSON object per line) is detected and folded into a FeatureCollection.
- TopoJSON (Topology) isn’t merged directly; convert it first: /maps/converters or /maps/topojson-minify.
Properties and geometry behavior
- Features are appended as‑is; geometry types are preserved.
- Property inclusion is user‑controlled via checkboxes; by default, all detected properties are included. “Include in all files” keeps only keys present across every loaded file.
- No attribute reconciliation/deduplication or topological union/dissolve is performed; this tool concatenates features.
- For further size reductions (precision, whitespace), use: /maps/geojson-minify.
Privacy
Everything runs client‑side in your browser. Files are not uploaded to a server. After the page loads, it even works offline.
Related tools
- GeoJSON Minifier: /maps/geojson-minify
- TopoJSON Minifier: /maps/topojson-minify
- Geo Format Converters: /maps/converters
- GeoJSON Editor: /maps/geojson-editor
Keywords (discoverability)
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