Batch File Renamer

The 'Batch File Renamer' is a completely free, browser-based tool that lets you drag and drop multiple files and rename them all at once using a flexible combination of rename rules. It supports 7 rule types: (1) Add prefix—prepend a string to the filename; (2) Add suffix—append a string before the extension; (3) Find & replace—swap one string for another; (4) Regex replace—use regular expression patterns for advanced replacements; (5) Sequential numbering—add numbers like 001, 002… with configurable start number and zero-padding; (6) Case conversion—switch between UPPER CASE, lower case, and Title Case; (7) Extension change—batch change file extensions (e.g., .jpg → .png).

You can stack multiple rules and apply them in order, so complex operations like 'add a prefix, number sequentially, and change the extension' become a single click. A real-time preview shows original and renamed filenames side by side, so you can verify every change before committing.

After renaming, download all files in a ZIP archive with their new names. All processing runs entirely within your browser's JavaScript engine—file data is never transmitted to any external server. Perfect for efficiently renaming large batches of files.