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Free Online GeoJSON Polyline Draw Tool

Draw polylines on an interactive map and export as GeoJSON LineString. Click to add vertices, double-click to finish. Copy or download GeoJSON. Free, no upload.

What is Polyline?

A GeoJSON LineString (commonly called a Polyline) is a sequence of two or more connected coordinate points forming a linear path. It is defined as 'type': 'LineString', 'coordinates': [[lng1,lat1], [lng2,lat2], ...]. Lines are used for roads, rivers, trails, flight paths, GPS tracks, routes, and any linear geographic feature.

How to draw

To draw a Polyline, select the Polyline mode. Click on the map to add each vertex. An orange preview line shows the path as you extend it. Double-click to finish the line. The resulting GeoJSON LineString contains all clicked vertices in order.

Common uses

LineString geometry is essential for route mapping, GPS track visualization, transportation networks, utility corridors, boundary lines, and any application that needs to represent linear geographic features.

GeoJSON output

Each geometry is converted to standard GeoJSON (RFC 7946) format with WGS84 coordinates. Copy or download the output for use in any GIS or mapping application.

All geometry types

This tool supports all 12 geometry types: Point, Polyline, Polygon, Freehand, StraightArrow, DiagonalArrow, DoveTailArrow, DoubleArrow, ClosedCurve, Sector, GatheringPlace, and PlotLineString.

Privacy

All drawing and GeoJSON generation happens entirely in your browser. No data is sent to any server. Your geographic data stays on your device.

Frequently Asked Questions

What is a GeoJSON LineString?
A LineString is an array of two or more coordinate pairs that form a connected path. It requires at least 2 points.
How do I finish drawing a line?
Double-click on the map to finish the line. The tool automatically generates the GeoJSON output.
How many vertices can I add?
There is no limit. Each click adds a vertex to the line.