Weirdly Useful
Bulk File Renamer
Preview cleaned, numbered filenames and download renamed copies.
Your data never reaches us
Nifty Utilities has no backend server, database, user accounts, or endpoint capable of receiving your tool inputs. Files and entries are processed inside your browser. We cannot view, capture, or store them.
How do you rename a batch of files with a consistent numbered prefix?
Organizing a folder of files with consistent, sequential names is a common task before uploading assets, archiving documents, or handing a set of files to someone else. This tool lets you define a prefix and a starting number, then previews the new names as a CSV so you can confirm them before downloading renamed copies.
How to use it
Select the files you want to rename and enter a prefix and a starting number. Click Preview renamed files to see a CSV mapping each original filename to its new name. The new names follow the pattern prefix-001.ext, prefix-002.ext, and so on, with the original file extension preserved in lowercase. Everything runs in your browser and your files are never uploaded to or stored by this site.
Tips
The preview CSV shows both the original and new names side by side, which is useful as a reference log after the rename. Files are numbered in the order they were selected, so organize or sort them in your file picker before selecting if order matters. The prefix is automatically converted to a URL-friendly slug, so spaces and special characters are replaced with dashes.
Frequently asked questions
Does the tool download renamed copies of the files?
The current version previews the new names as a downloadable CSV. You can use the CSV as a reference to rename the files using your operating system or a script. This approach lets you verify the mapping before committing any changes.
What happens if two files end up with the same new name?
Because files are numbered sequentially, each new name is unique as long as each selected file gets its own position in the list. The CSV preview makes it easy to spot any collisions before acting on the output.
Important
This tool provides estimates and general-purpose documents, not financial, tax, legal, or professional advice. Verify important results before relying on them.
Support
Problem with this tool or suggestions for improvement? Please email support@niftyutilities.com.