The Map Extent Helper from the National Geologic Map
Database Project lets users sketch a variety of geometry types to return the
object extent in a variety of formats. The utility was originally developed for the librarian and
archivist community to assist in capturing coordinate extents (particularly MARC formats) for use in
metadata input. The utility was later extended to serve a larger community with additional output
formats like GeoJSON, KML, CSV, and ISO/FGDC metadata. If you would like to suggest support for
other formats, submit a request for
more output formats.