RENCASE — Change the case of filenames.

Syntax:
RENCASE /A:attribs /E /L /N /N:flags /S /U /W /X:luw /[range] file…

/A:attribsfilter by attributes
/Eno error messages
/Lchange the base name (all but the extension) to lowercase
/Nnot really
/N:flagsD no hidden directories, J no junctions, Z no system directories
/Slook in subdirectories for matching files
/Uchange the base name (all but the extension) to uppercase
/Wchange the base name (all but the extension) to word case
/X:luwchange the extension to upper/lower/word case
/[range]many range options are supported
file…wildcards, directory aliases, etc. supported

RENCASE renames files, changing the case of letters. Filenames are handled as two parts: the base name (everything before the last period), and the extension (everything after). Options /L, /U, and /W affect the base name, and /X: affects the extension.

If no action is specified (none of /L, /U, /W, or /X:), the default is /L.

rencase /l /x:l *.html