Data shall be supplied in WGS84 (epsg:4326) otherwise go for searching your epsg
If your data is projected in an EPSG other than 4326, use the textbox below to search and select the desired EPSG
In the case of geojson. If EPSG is clarified within geojson , this should overwrite the one typed and found(if any)
Parser should do the reprojection for you. (all data will be reprojected to EPSG:3857, which is the default map projection)