Bulk rename files with preview
Renamio shows the original and new name for each file. Check the results and adjust your rules before applying the rename.
What usually goes wrong
- A small rule mistake can damage hundreds of file names.
- Extension changes are easy to apply too broadly.
- Duplicate output names are hard to see without a full preview.
Renamio workflow
- 1Build the rename rules and inspect the old-to-new preview table.
- 2Look for unchanged files, unexpected extensions, and duplicate final names.
- 3Adjust rules until the preview is predictable.
- 4Apply locally and keep history available for review.
Why this workflow helps
- Catches mistakes before real files change
- Makes rule stacks easier to trust
- Useful for non-technical teammates reviewing a batch
Good fit
- Large folders
- Client delivery files
- Extension and sequence cleanup
Not the right fit
- Blind one-line scripts
- Single-file renames
- Changing file contents
Related rename tools
Extension repair
Fix incorrect file extensions
Detect real file types and fix misnamed extensions such as zip111, rar001, and damaged archive suffixes.
Numbering
Add sequential numbers to file names
Batch add padded sequence numbers, custom prefixes, and ordered numbering to photos, documents, exports, and project files.
Text replacement
Find and replace text in file names
Batch replace spaces, camera prefixes, duplicate markers, and repeated text in file names with live preview and undo protection.
Related guides
Batch rename guide
How to batch rename files
Learn a practical batch rename workflow: choose files, build simple rules, preview every result, check duplicates, and apply changes locally.
Open guideMulti-file workflow
Rename multiple files at once
Rename many files at once with local preview, reusable rules, sequence numbers, text cleanup, and undo-oriented history.
Open guideRenamio for Windows
Free batch file renamer for Windows
Download Renamio free on Windows to batch rename files locally with preview, rule stacking, sequence numbers, cleanup, and history.
Open guideFAQ
Why is preview important for batch renaming?
Because a rule applies to many files at once. Preview lets you verify the final output and catch collisions before files are changed.
Can preview help with duplicate names?
Yes. A preview-first workflow makes duplicate final names visible before applying the batch.
Preview the rename before changing files
Use Renamio locally on Windows or macOS to test the naming pattern, catch collisions, and keep rename history for review.