GeoConvert converts geodata files (KML, KMZ, GPX, GeoJSON, CSV, zipped Shapefile) between formats and coordinate systems entirely in your browser. No file is ever uploaded: parsing and conversion run client-side, so zero bytes of file content reach a server. Reprojection covers WGS84, SWEREF99 TM, all 12 SWEREF99 local zones, and RT90 2.5 gon V, systems most general-purpose converters barely support. Free, no signup, no account needed.