About Bulk File Renamer -- Rename Multiple Files at Once
Generate a ready-to-run script to bulk rename files on your PC. Configure renaming rules, preview changes, and rename hundreds of files in seconds.
How to use
- Pick your target folder using the chips at the top -- Desktop, Downloads, Documents, or Custom. Choose Custom to paste a full path like
C:\Users\You\Photos on Windows or /Users/you/Pictures/Trip on macOS. The tool only generates a script for that folder, so be specific -- pointing at C:\Users\You would try to rename everything in your home directory.
- Narrow the scope with a file type filter. The chips cover the common cases (
*.jpg, *.png, *.pdf, *.mp3, *.mp4) and Custom lets you type your own pattern like *.txt or *.heic. This is essential when a folder mixes photos, raw camera files, and edits -- you can rename just the JPGs without touching the originals.
- Toggle the renaming operations you need. Each operation has its own row: Prefix (e.g.
2025_), Suffix (e.g. _final), Find & Replace (e.g. find IMG_, replace with vacation-), Numbering with start value, padding digits, and prefix/suffix position, and Case (lowercase, UPPERCASE, or Title Case). You can stack multiple at once -- a real example: turn IMG_0001.jpg into vacation-2025-01.jpg by combining Find & Replace with a 2-digit Numbering suffix.
- Set your numbering carefully if you are sequencing files. Start at
1, padding 3, position Suffix produces -001, -002, -003 appended to each filename in folder order. Bump padding to 4 if you have more than 999 files so they sort correctly in Explorer or Finder.
- Watch the live preview in the right-hand panel as you adjust rules. It shows the original filename next to the new one for every file in the target folder, so you can verify nothing collides and the pattern reads the way you expect. Reorder rules or tweak values until the preview looks right -- this is the safest step in the whole workflow.
- Pick your OS tab above the script -- Windows (PowerShell), macOS (Bash), or Linux (Bash). The generated script uses native commands (
Rename-Item, mv) and handles spaces and special characters in filenames automatically. Click Copy Script to copy or Download Script to save it as a .ps1 or .sh file.
- Run the script in your terminal. On Windows, open PowerShell, paste the script, and press Enter. On macOS or Linux, open Terminal, paste, and run -- you may need to
chmod +x the file first if you saved it. The script renames sequentially and prints each change as it goes. Save the terminal output to a text file before running if you want a manual rollback log.
Frequently asked questions
Does this tool rename my files directly?
No -- this tool never touches your filesystem. It generates a script (PowerShell, Bash, or Batch) that you copy and run on your own computer. Every rename operation is visible in the script before you execute it, so you have full control over what changes. This approach is safer than tools that rename files directly, because you can review, edit, or cancel the script at any point. If you want to test the script first, you can add an echo/dry-run flag to see what would happen without actually renaming anything.
What renaming rules can I configure?
The tool supports six types of renaming rules that can be combined freely. Add a prefix (like 2026-04_) or suffix (like _final) to every filename. Use find-and-replace to swap specific text -- for example, replacing spaces with underscores or correcting a misspelled word across all files. Insert sequential numbers with configurable start value, step, and zero-padding (e.g., 001, 002, 003). Change file extensions to convert between formats or fix incorrect extensions. Convert case to make filenames consistently uppercase, lowercase, or title case. Rules are applied in the order you add them, so a replace rule followed by a prefix rule works exactly as you would expect.
Which operating systems are supported?
The tool generates scripts for three platforms: Windows PowerShell (recommended for Windows 10 and 11), Windows Batch (for older systems or users who prefer cmd.exe), and Bash (for macOS, Linux, and Windows Subsystem for Linux). Each script uses native OS commands -- PowerShell uses Rename-Item, Batch uses ren, and Bash uses mv. No additional software or dependencies are needed. Simply choose your OS from the dropdown, and the generated script will be formatted with the correct syntax, path separators, and quoting conventions for your platform.
Can I undo a bulk rename?
The generated script does not include a built-in undo command, but you can create your own rollback. Before running the rename script, copy the preview output showing the original filenames and save it to a text file. If you need to revert, you can use this tool again with the find-and-replace rule to reverse the changes -- for example, removing a prefix you just added or swapping back the text you replaced. For critical folders, consider making a backup copy of the directory before running any rename operation.
How do I rename files with special characters or spaces?
The generated scripts automatically handle filenames containing spaces, parentheses, brackets, and most special characters by wrapping paths in quotes. On PowerShell, filenames are enclosed in single quotes; on Bash, they use double quotes with proper escaping. However, filenames with extremely unusual characters (like newlines or control characters) may require manual editing of the script. If you see an error during execution, check the specific filename causing the issue and rename it manually first before re-running the batch script.
Is there a limit to how many files I can rename at once?
There is no hard limit imposed by this tool -- the generated script can handle thousands of files in a single run. The practical limit depends on your operating system. PowerShell and Bash can process tens of thousands of rename operations without issues. If you are working with an extremely large directory (100,000+ files), the script may take a few minutes to execute, but it will complete reliably. For very large batches, consider running the script in a dedicated terminal window so you can monitor progress.
Can I use this for organizing photo or music libraries?
Absolutely -- bulk renaming is one of the most common tasks for organizing media libraries. For photos, you can add date prefixes to sort images chronologically, insert sequential numbers for album ordering, or replace camera-generated names (like
IMG_ or
DSC_) with descriptive names. For music files, you can standardize naming conventions by converting to title case, replacing underscores with spaces, or adding artist prefixes. Pair this tool with the
Duplicate File Finder to clean out duplicate photos or songs before renaming.
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