# rnm > Bulk Rename Utility. > More information: . - Replace a search string with a replacement string in filenames: `rnm -ss {{old}} -rs {{new}} {{path/to/directory}}` - Use a fixed (literal) search and replace string instead of regex: `rnm -ssf {{old}} -rs {{new}} {{path/to/files}}` - Add an auto-incremented index to filenames starting from 1: `rnm -i 1 -inc 1 -rs {{_}} {{path/to/files}}` - Rename files using a list of new names from a text file: `rnm -ns/f {{path/to/names.txt}} {{path/to/files}}` - Rename only files (ignoring directories and links): `rnm -fo -ss {{pattern}} -rs {{replacement}} {{path/to/files}}` - Sort input files by modification time before renaming: `rnm -s/mt -ss {{pattern}} -rs {{replacement}} {{path/to/files}}` - Run a simulation without making actual changes: `rnm -sim -ss {{pattern}} -rs {{replacement}} {{path/to/files}}` - Undo the last renaming operation: `rnm -u`