File Renamer

How to use the file renamer

1. Choose files, or paste a list of names.
2. Set the rules — find and replace, case, numbering, extension.
3. Take the script, or download renamed copies.

About this tool

A web page cannot rename a file on your disk. Every tool that claims to is either downloading copies under new names or misleading you, so this does the honest version of both: it plans the rename, shows every old name beside its new one, and hands the result back as renamed copies or as a script you run where the files actually are.

The script is the better route for anything beyond a handful. It renames in place rather than filling a downloads folder with duplicates, it keeps the original files' dates, and it works on files too large or too numerous to pass through a browser at all. Both `sh` and PowerShell are generated, with the flags that refuse to overwrite.

Collisions are the failure that quietly loses data — two files renamed to the same thing, and one of them is gone. They are reported rather than resolved by silently adding a suffix, because a renamer that invents a name to avoid a collision is making a decision that should be yours.

Windows reserved device names are flagged for the same reason. A file called `con.txt` or `aux.log` cannot exist on Windows regardless of what created it, and a rename that produces one fails at the point of use rather than here.

Only the names are read. The file contents are never opened unless you ask for renamed copies, and nothing is uploaded in any case.

Common uses

• Renaming a folder of camera files into something meaningful.
• Numbering a sequence of files consistently.
• Normalising names to lowercase and hyphens before publishing.

Frequently asked questions

Can it rename the files on my computer?

No — no web page can. It produces a script that does, or downloads renamed copies. The script is the better option for more than a handful of files.

What happens if two files end up with the same name?

It is reported as a problem rather than resolved. Inventing a suffix to avoid a collision is a decision that should be yours, and silently overwriting loses a file.

Are my files uploaded?

No. Only the names are read; the contents are only touched if you ask for renamed copies, and even then everything stays in the browser.