Bulk File Renamer Preview
File
Drop a folder's worth of files and the tool shows the rename it would do — without touching a single file. Patterns use familiar placeholders (`{n}` numbered with zero-padding, `{name}` original base, `{ext}` original extension, `{date}` from each file's last-modified timestamp). Layered on top: a find/replace pass, three case modes, and a colliding-output detector that turns dupe rows red so you spot the conflict before you copy the result list. Files never leave the browser — the preview is built from File API metadata, no upload, no API call.
How to use
- Drop or pick files. The list populates with their current names.
- Pick a preset or write your own pattern with `{name}`, `{n}`, `{ext}`, `{date}`.
- Copy the old→new table as TSV to feed `mv`, PowerShell, or your file manager's batch rename.
Frequently asked questions
- Does it actually rename my files?
- No. Browsers can't write back to your filesystem from a regular page — this is a preview tool. Copy the table and apply it with `mv`, `pwsh Rename-Item`, or your file manager.
- Where does `{date}` come from?
- Each file's `lastModified` field as the browser sees it (`YYYYMMDD`). For uploaded files this is the OS-reported modification time, not when you uploaded them.
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