Bulk File Renamer
Rename dozens of files at once — add a prefix, strip camera codes, auto-number a batch, or change case. Everything runs in your browser. Download a ZIP with all files renamed.
Drop any files here, or click to browse
Files stay in your browser — nothing is uploaded
Rename rules
Drop files above, configure rules, then download the renamed ZIP.
Common use cases
Clean up camera exports
Strip DSC_ or IMG_ prefixes from camera filenames and replace them with a meaningful project name.
Number a photo batch
Pad-number a folder of images for a client gallery: 001_photo.jpg, 002_photo.jpg…
Normalize casing
Convert a mixed-case file dump to lowercase for a web server that treats filenames as case-sensitive.
Batch prefix for delivery
Add a project code or date prefix to every deliverable before handing off to a client.
Frequently asked questions
Are my files uploaded anywhere?
No. All processing happens entirely in your browser using JavaScript. Your files never leave your device — they are read locally, renamed in memory, and packaged into a ZIP file that is downloaded directly to you.
What rename operations are supported?
You can: add a text prefix or suffix, find-and-replace text within filenames (with optional case sensitivity), change the case of the base name (lower, upper, title, sentence), and auto-number files with configurable start, step, zero-padding, separator, and prefix or suffix placement. Rules are applied in order: replace → case → number → prefix/suffix.
Does renaming affect the file extension?
No. All rules operate on the base name only — the extension (e.g. .jpg, .pdf, .txt) is always preserved unchanged. The only exception is case transform, which also keeps the extension as-is.
What happens if two files end up with the same name?
The tool automatically detects collisions and appends _2, _3, and so on to duplicate output names so your ZIP never has conflicting files.
Can I rename files without downloading them again?
The ZIP contains your files with the new names but the same content — nothing is re-compressed or re-encoded. For most file types the content is byte-for-byte identical to the original.
Is there a file count or size limit?
There is no hard cap. The tool processes everything in your browser, so the practical limit is your device's available RAM. Batches of a few hundred files work fine for typical use.
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