Drop a .gmd or a .gdlvl file. The tool detects which one it is from the contents and gives you the other. Everything runs in your browser, so the level never leaves your device.
How the two formats relate
.gdlvl
base64url( gzip( the whole .gmd XML ) )
.gmd
XML plist, where k4 = base64url( gzip( level string ) )
Converting adds or removes one wrapper. The level data inside is never touched.
Drop files here
.gmd and .gdlvl, any number at once