Batch File Renamer

Applies a stack of rename rules to a list of filenames (one per line) and shows a live preview table with character-level diffs highlighting what changed. The tool only generates the new names; it does not touch your actual files.

1. Paste filenames into the File Names textarea, one per line. 2. Configure rules in the Rename Rules card (any combination is allowed). 3. Watch the Preview table update live: green highlights mark rows that changed. 4. Click Copy Renamed List to put the new names on the clipboard.

Rules run in this sequence: (1) Find & Replace, with an optional Regex toggle - when off it is a literal string split-join; (2) Add Prefix; (3) Add Suffix, inserted before the extension; (4) Change Case (none / lowercase / UPPERCASE / Title Case); (5) Add Sequential Numbers with configurable Start and Padding width (prepended as NNN_name); (6) Remove Pattern, always a regex applied last. Invalid regexes are silently skipped. Extensions are preserved throughout.