GeoJSON Buffer Zone Generator: Add Multiple Buffer Rings Online

This free online GeoJSON buffer zone generator lets you upload any GeoJSON file and instantly create one or more buffer rings around your geometries — directly in your browser, with no software to install. Set each buffer zone to any distance in meters, kilometers, miles, or feet, pick a color for each ring, and download the result as a ready-to-use GeoJSON file.

How to Use the GeoJSON Buffer Zone Generator

Step 1: Load Your GeoJSON

Drag and drop a .geojson or .json file onto the upload area, or click to browse. You can also switch to the Paste GeoJSON tab and paste raw GeoJSON text directly. The tool accepts any valid GeoJSON type: Feature, FeatureCollection, Point, LineString, Polygon, MultiPolygon, and mixed collections. Your geometry will appear on the map immediately, highlighted in yellow.

Not sure what your GeoJSON looks like? Hit Load Sample to load a polygon of central London and explore the tool before using your own data.

Step 2: Configure Your Buffer Zones

Each buffer zone is a separate ring. The tool starts with one ring pre-configured at 1 kilometer. You can:

• Change the distance value to any positive number
• Switch the units between meters, kilometers, miles, and feet
• Pick a color for each ring using the color swatch
• Click + Add Buffer Zone to create additional concentric rings at different distances
• Remove any ring with the × button

Each ring is independent — you can mix units across rings, for example a 500-meter ring and a 2-mile ring on the same geometry.

Step 3: Generate and Review

Click Generate Buffers. The buffer zones render on the map in their chosen colors, largest first so smaller rings remain visible on top. The results panel below the map shows the area of each buffer zone in units matching your input, plus conversions to other common units (hectares, acres, km², mi²).

Step 4: Download

Click Download GeoJSON to save a FeatureCollection containing your original geometry and all buffer zones as separate features. Each buffer feature includes properties recording the distance, units, color, and area in multiple unit systems. You can also click Copy GeoJSON to copy the output directly to your clipboard.

What Is a GeoJSON Buffer Zone?

A buffer zone is an area that extends outward from a geometry by a fixed distance in all directions. Buffering a point produces a circle. Buffering a line produces a corridor along its length. Buffering a polygon expands all its edges outward uniformly. The result is always a polygon (or multipolygon for complex inputs).

GeoJSON is an open geographic data format based on JSON, widely used in web mapping, GIS applications, and spatial analysis. Buffer calculations on GeoJSON data are performed using geodesic math that accounts for the curvature of the Earth, so the distances are accurate regardless of where on the globe your geometry is located.

This tool uses Turf.js, an open-source JavaScript library for geospatial analysis, to calculate buffers entirely in your browser. Your data is never sent to any server.

Common Use Cases

Environmental Impact Assessment

Create 100m, 500m, and 1km buffer zones around a proposed development site to identify which environmental features, habitats, or sensitive areas fall within each impact zone.

Service Area Planning

Buffer a set of facility locations (schools, hospitals, shops) to visualize catchment areas at different travel distances. Multiple rings let you distinguish between close, medium, and outer service zones in a single operation.

Wildlife and Conservation

Generate protection buffer zones around wildlife corridors, nesting sites, or protected areas. The downloadable GeoJSON output can be loaded directly into QGIS, ArcGIS, or any other GIS tool for further analysis.

Property and Land Use

Buffer a parcel boundary to identify neighboring properties within a given setback distance, or check compliance with planning regulations requiring a minimum distance from certain features.

Emergency Planning

Create evacuation or exclusion zones around a point of interest such as a facility, incident location, or infrastructure asset at standard distances (e.g., 1/4 mile, 1/2 mile, 1 mile).

About the Output GeoJSON

The downloaded file is a standard FeatureCollection. Original input features are included with a _layer: "source" property. Each buffer feature carries these properties:

• _layer: “buffer”
• bufferIndex: ring number ordered from smallest to largest
• bufferDistance: the distance value you entered
• bufferUnits: the units you selected
• bufferColor: the hex color assigned to the ring
• areaM2: total buffer area in square meters
• areaKm2: total buffer area in square kilometers
• areaHa: total buffer area in hectares
• areaAcres: total buffer area in acres

Each buffer feature represents the full buffered area (a cumulative disk, not a donut ring), which is the standard representation expected by GIS software. To get ring-only geometry between two buffer distances, compute the difference in QGIS (Vector > Geoprocessing > Difference) or using the Turf.js difference function.

Frequently Asked Questions

What GeoJSON geometry types are supported?

All standard GeoJSON geometry types: Point, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon, and GeometryCollection. Mixed FeatureCollections containing different geometry types will all be buffered and merged into the output.

How accurate are the buffer distances?

Buffers are calculated using geodesic math via Turf.js, which models the Earth as a sphere. This is accurate to within a fraction of a percent for most practical distances. For very large buffers (hundreds of kilometers) or areas near the poles, a full ellipsoidal calculation as used in desktop GIS software would give marginally more precise results.

Can I buffer a GeoJSON file with multiple features?

Yes. If your FeatureCollection contains multiple features, all of them will be buffered by each ring distance. The buffer around each feature is calculated independently, which means features that are close together may produce overlapping buffers in the output.

What is the difference between a buffer and a radius?

A radius tool draws a circle from a single point. A buffer works on any geometry: it expands polygons, creates corridors along lines, and produces circles from points. If you need a simple radius circle from a coordinate, the Radius Mapping Tool is purpose-built for that.

Can I use the output in QGIS or ArcGIS?

Yes. The downloaded .geojson file can be dragged directly into QGIS or imported into ArcGIS Pro via Add Data. The feature properties (area, distance, units) will be available as attribute columns in the layer table.

Is my data kept private?

All processing happens locally in your browser using JavaScript. No data is uploaded to any server. Your GeoJSON file stays on your device throughout the entire process.

What is the maximum file size?

There is no enforced file size limit, but very large GeoJSON files (tens of megabytes with thousands of complex polygons) may slow down buffer generation because all calculations run in the browser. For very large datasets, consider simplifying your geometry first using the Vector Simplifier Tool before buffering.