Draw points, lines and polygons directly on the map, or upload a CSV, GeoJSON file or zipped Shapefile, then generate a buffer zone around any of them at a distance and unit you choose. Manage every layer independently and export the result as GeoJSON — instantly, in your browser, with no software required. Open full screen ↗
Turn Any Shape Into a Buffer Zone
A buffer zone is the area within a fixed distance of a point, line or polygon — a 500-metre safety radius around a pipeline, a 5-kilometre catchment ring around a store, or a 50-foot setback along a property line. This tool lets you build that source geometry on the map or import it from a file, then generate the buffer polygon around it with one click.
Two Ways to Build Your Source Layer
Add the geometry you want to buffer using either method below, or combine both across multiple layers in the same session:
- Draw on the map: Click "Point", "Line" or "Polygon" in the toolbar, then click the map to place vertices. Finish a line or polygon by double-clicking, pressing Enter, or clicking "Finish" — every shape you draw is added to a single "Drawn Shapes" layer.
- Upload a file: Click "Upload" or drag a file onto the map — a CSV of coordinates (latitude/longitude columns auto-detected), a GeoJSON/.json file, or a zipped Shapefile (.zip containing .shp, .dbf and .shx). Each upload becomes its own layer.
Once you have at least one layer, choose it as the "Target Layer", set a distance, unit and buffer colour, then click "Generate Buffer". The new buffer polygon appears as its own layer, ready to restyle, export, or buffer again.
Common Use Cases
🥾
Route Corridor Analysis
Draw or upload a route or trail as a line and buffer it to define a corridor for planning, permitting or impact assessment.
🏬
Store & Facility Catchment Areas
Mark a store, warehouse or facility location and buffer it to estimate a straightforward radial catchment or delivery zone.
🛢️
Pipeline & Infrastructure Safety Zones
Draw or upload a pipeline, power line or road centreline, then buffer it to visualise a required safety or easement distance along its full length.
🌿
Environmental & Wildlife Buffers
Buffer a wetland, water body or habitat boundary to show a protective buffer zone required by environmental regulations.
📡
Sensor & Coverage Range Mapping
Plot sensor, antenna or camera locations from a CSV and buffer each one to visualise its effective coverage radius.
📐
Property Setbacks & Boundaries
Upload a parcel boundary as GeoJSON or a Shapefile and buffer it inward or outward to visualise a required setback or expansion margin.
Buffer Controls
Three settings in the sidebar control how each buffer is generated:
- Target Layer: pick any layer currently on the map — a drawn shape, an uploaded file, or even a previously generated buffer — as the source to buffer.
- Distance & Unit: set the buffer radius in meters, kilometers, miles, feet or yards.
- Buffer Color: sets the outline and fill colour of the new buffer layer, distinguishing it at a glance from source layers.
Every generated buffer becomes its own independent layer, so you can compare several distances side by side without losing the original geometry.
Exporting Your Buffer Zones
Two export options are always available in the sidebar:
- Export a single layer: click the download icon next to any layer in the Layers panel to save just that layer's GeoJSON.
- Download All Layers: combines every layer currently on the map — source geometry and buffers alike — into one GeoJSON FeatureCollection, with each feature tagged with its layer name.
GeoJSON is read natively by Leaflet, Mapbox GL JS, QGIS and ArcGIS, and renders directly as an interactive map on GitHub.
Understanding Buffer Zones
Buffering works the same way regardless of what you start with: every point on the source geometry is expanded outward by the same distance, and the resulting outline is merged into a single smooth polygon (or multi-polygon, if the buffered shapes don't touch).
Distance, Units and Geodesic Accuracy
Set the buffer distance in meters, kilometers, miles, feet or yards. The calculation accounts for the Earth's curvature (a geodesic buffer), so distances stay accurate whether you're buffering something a few metres wide or spanning hundreds of kilometres.
Points, Lines and Polygons Buffer Differently
A point buffers into a circle. A line buffers into a stadium-shaped corridor running along its full length. A polygon buffers into a larger polygon with the same outline pushed outward — useful for expanding a boundary or adding a safety margin around a restricted area.
Watch: Buffer Zone Generator in Under a Minute
Prefer to watch instead of read? This short walkthrough covers adding a point, line, or polygon and generating a buffer zone around it.
Frequently Asked Questions
Can I generate more than one buffer from the same source layer?
Yes. Select the same target layer multiple times with different distances, and each run adds a new, independent buffer layer to the map, so you can compare several distances side by side.
What is a buffer zone, in simple terms?
A buffer zone is the area that lies within a fixed distance of a point, line or polygon. Buffering a point produces a circle; buffering a line produces a corridor running along its length; buffering a polygon produces a larger polygon with the same outline pushed outward by that distance.
Is my drawn, uploaded or buffered data sent to a server?
No. Drawing, file parsing and buffer calculations all run entirely in your browser using the Turf.js geometry library. Nothing is uploaded to or stored on any server, which makes this tool safe to use with sensitive or private location data.
Why does my buffered line look like a rounded-end corridor instead of a rectangle?
That's expected — buffering a line produces rounded ends and rounded outer corners at every bend, since every point along the line (including its endpoints) is expanded outward by the same distance in every direction.
Can I change a layer's colour or delete it after it's created?
Yes. Every row in the Layers panel has a live colour swatch, a zoom-to-bounds button, an individual GeoJSON export button, and a delete button — all of which apply instantly without affecting other layers.
What does a zipped Shapefile upload need to contain?
A single .zip file containing at minimum the .shp, .dbf and .shx components of the Shapefile. Multiple layers inside one .zip are all loaded as separate, individually manageable layers.
What distance units are supported?
Meters, kilometers, miles, feet and yards. The buffer distance is calculated geodesically, accounting for the Earth's curvature, so it stays accurate at both small and large scales.
Can I buffer an uploaded Shapefile or GeoJSON file, not just something I draw?
Yes. Any layer on the map — whether drawn by hand, uploaded from a CSV, GeoJSON file or zipped Shapefile, or even a buffer you generated earlier — can be selected as the Target Layer and buffered again.
What does the exported GeoJSON file contain?
Exporting a single layer downloads just that layer's features. "Download All Layers" combines every layer currently on the map into one FeatureCollection, with each feature tagged with the name of the layer it came from.
What format does my CSV file need to be in?
A standard comma-separated CSV with a header row, including one column for latitude and one for longitude. Common header names like lat, latitude, y, lon, lng, long, or longitude are detected automatically, with a manual column selector if detection fails.
Step-by-Step Guide
1Step 1
Open the tool
The map loads centred on the world with no layers yet. The floating toolbar offers drawing tools, My Location, file upload and a basemap switcher; the sidebar holds the buffer generator, layer manager and export options.
2Step 2
Draw a point, line or polygon
Click "Point", "Line" or "Polygon", then click the map to place vertices. Finish a line or polygon with a double-click, the Enter key, or the Finish button. Every shape lands in a shared "Drawn Shapes" layer.
3Step 3
Or upload a file instead
Click "Upload" or drag a file onto the map — a lat/lng CSV, a GeoJSON file, or a zipped Shapefile. The tool auto-detects the geometry and adds it as a new layer, zooming the map to fit it.
4Step 4
Choose a target layer
Open the "Target Layer" dropdown in the sidebar and pick the layer you want to buffer — any drawn shape, uploaded file, or even an existing buffer.
5Step 5
Set the distance, unit and colour
Enter a buffer distance, choose meters, kilometers, miles, feet or yards, and pick a buffer colour.
6Step 6
Generate the buffer
Click "Generate Buffer". The tool computes a geodesic buffer polygon around your target layer and adds it as a new layer, then zooms the map to fit it.
7Step 7
Manage your layers
In the Layers panel, toggle any layer's visibility, recolour it live, zoom to its bounds, or delete it. Buffer layers are labelled distinctly from source layers.
8Step 8
Buffer again if needed
Select a different target layer, or even a buffer you just created, and repeat with a new distance to compare multiple buffer rings at once.
9Step 9
Export your results
Download an individual layer as GeoJSON from its row in the Layers panel, or click "Download All Layers" to export every layer on the map in a single GeoJSON file.
Managing Your Layers
Every shape you draw or upload, and every buffer you generate, appears as a row in the Layers panel. Each row lets you toggle visibility with a checkbox, recolour the layer live with a colour swatch, zoom the map to its bounds, export it individually as GeoJSON, or delete it — all without affecting any other layer.
Related Tools
Map tiles © OpenStreetMap contributors and Protomaps (hosted by KONAKTIVE), CARTO, Esri (satellite). Buffer geometry powered by Turf.js. CSV parsing by PapaParse, Shapefile parsing by shpjs. Map rendering by Leaflet. All drawing, file parsing and buffer computation is local — no data is uploaded to any server.
