Bulk File Renamer
Drop in a batch of files and build a rename pattern from find-and-replace, prefixes, suffixes, case changes, and sequential numbering, with a live preview before downloading every renamed file in one .zip.
Drop files to rename
Add files to preview their new names.
Preview
Add files to preview their new names.
How to bulk rename files
Drop in a batch of files, build a rename pattern, and download every file under its new name in one .zip — all processed locally in your browser.
Building a rename pattern
Combine a find-and-replace (plain text or a regular expression), a prefix, a suffix, and a case transform. Every change applies to the file's base name only — the extension is handled separately by the "Keep original extension" option, so a find-and-replace can't accidentally mangle a file's .jpg or .pdf.
Sequential numbering
Numbering counts up from the order files currently appear in the list, starting at whatever number you set, with as many leading zeros as the "Digits" setting asks for. Removing a file renumbers everything after it, since the count is always based on the current list, not when each file was added.
Conflicts and downloading
If a pattern produces the same name for two or more files, every affected row is flagged and the download button is disabled until the pattern no longer collides. Once every result is unique, "Download all as .zip" bundles every file under its new name into a single archive.
Processing notes
Files are read and renamed entirely in your browser using their in-memory bytes; nothing is uploaded anywhere, including the file names themselves.
FAQ
Does this change the files, or just what they're called?
Only the file name changes. The bytes inside each file are copied unchanged into the downloaded .zip.
Can I use a regular expression in Find?
Yes. Turn on "Treat Find as a regular expression" and the Find field is compiled as one, with every match replaced.
What happens if my pattern is an invalid regex?
Affected names are left unchanged in the preview rather than the tool breaking, so you can keep editing the pattern until it's valid.
Can I rename just one file?
Yes, though for a single file the Case Converter or a plain rename in your file manager is usually just as fast — this tool's advantage is doing dozens of files at once.