Sequential File Renamer
Sequential File Renamer assigns numbers beginning at 001 in the order the browser supplies the selected files. It uses the entered base name or file when blank, adds a hyphen and a minimum three-digit padded sequence, preserves each final extension, and packages copies in renamed-files.zip. It cannot sort by name, date, or natural number, preview mappings, choose a start value, or prevent collisions.
Runs locally — files stay on your deviceWhat determines numbering order?
The selected FileList order exposed by the browser.
Padded sequences sort predictably within their width
Numbers 001 through 999 share three characters. Values beyond 999 continue naturally rather than being truncated.
How it works
Each zero-based selection index becomes index plus one, padded to at least three digits, and appended to the base before the final extension.
Key concepts
Order is input order
The page performs no explicit sorting.
Minimum three digits
The sequence is padded to length three but can grow longer.
When to use it
- Number an already ordered photo batch.
- Create consistent flat names for export.
- Replace unrelated basenames while preserving ordinary extensions.
When not to use it
- Do not assume the browser sorted by date or natural filename order.
- Do not expect a custom starting number.
- Do not use it where external links depend on old names without a mapping.
Worked examples
Photo set
- Input
Base trip; three JPGs- Expected output
trip-001.jpg through trip-003.jpg
Each extension is retained.
Blank base
- Input
Two PDFs- Expected output
file-001.pdf and file-002.pdf
file is the fallback.
Mixed types
- Input
PNG then TXT- Expected output
base-001.png, base-002.txt
Extensions remain per file.
Common mistakes
Assuming chronological sort
No metadata sort occurs. Correction: Prepare selection order first.
Expecting a mapping report
Only the ZIP is returned. Correction: Record mappings separately when needed.
Ignoring collisions
Existing or duplicate target names are unchecked. Correction: Use a unique base and inspect output.
Best practices
- Arrange and verify input order.
- Use a portable, descriptive base.
- Keep a mapping when downstream references matter.
Related operations and differences
Add Prefix to Filenames
Choose Add Prefix to Filenames when you need to add a prefix to selected filenames.; use Sequential File Renamer specifically for rename sequential.
Add Suffix to Filenames
Choose Add Suffix to Filenames when you need to add a suffix before every extension.; use Sequential File Renamer specifically for rename sequential.
Compare Two Files
Choose Compare Two Files when you need to compare two files securely by SHA-256.; use Sequential File Renamer specifically for rename sequential.
File Checksum Comparator
Choose File Checksum Comparator when you need to compare a file digest with an expected checksum.; use Sequential File Renamer specifically for rename sequential.
File Hash Calculator
Choose File Hash Calculator when you need to calculate a local cryptographic file digest.; use Sequential File Renamer specifically for rename sequential.
File Size Calculator
Choose File Size Calculator when you need to inspect exact and human-readable file sizes.; use Sequential File Renamer specifically for rename sequential.
Limitations and privacy
- No sorting, start number, step, width control, mapping preview, collision handling, path preservation, or in-place rename.
- Simple last-dot extension logic.
- Output is renamed-files.zip.
Processing happens in this browser. Selected file contents are not uploaded by this tool.
Downloads and copied results remain on this device; handle them according to their sensitivity.
Frequently asked questions
Where does numbering start?
At 001.
Can I choose four digits?
No; padding is fixed to a minimum of three.
Are extensions retained?
Yes.
Are originals changed?
No.