GeoJSON is a format for encoding a variety of geographic data structures. GeoJSON is an open standard geospatial data interchange format that represents simple geographic features and their nonspatial attributes. It uses a geographic coordinate reference system, World Geodetic System 1984, and units of decimal degrees.
There are two options:
Basic
Projected
A regular GeoJSON uses unprojected coordinates (geographic coordinate system), like latitude and longitude, to represent data on a spherical model of the Earth, while a projected GeoJSON contains coordinates that have been transformed (projected) from that sphere onto a flat, 2D surface using a mathematical map projection. Therefore, a regular GeoJSON is a spherical dataset, while a projected GeoJSON is a planar dataset ready for display on a map.
Access the export menu via the main menu (☰) → Export
Click (☰) → `Export` → `GeoJSON (GIS format)`
Click (☰) → `Export` → `Projected GeoJSON (in meters)`
A .json file will be downloaded to your computer. This file can be opened with any GeoJSON viewer or imported into another program that consumes that format.