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
- Start by selecting a target folder -- Desktop, Downloads, Documents, or enter any custom path on your system. If you are organizing files from a camera import or a project folder, type the full directory path to target exactly the right location. The tool works with any folder your user account can access.
- Configure your renaming rules to match your needs. You can add prefixes (like a date or project name), append suffixes, find and replace specific text within filenames, insert sequential numbers for ordering, change file extensions, or convert the entire filename to uppercase, lowercase, or title case. Multiple rules can be stacked together -- for example, replacing spaces with hyphens and adding a date prefix in one operation.
- Before generating any script, use the live preview to see exactly how each filename will change. The before-and-after comparison shows every file in the target folder so you can catch mistakes, confirm the naming pattern looks right, and verify that no files will accidentally collide with the same name. This step is critical when renaming hundreds of files at once.
- Once you are satisfied with the preview, copy the generated script and paste it into your terminal. On Windows, use PowerShell or Command Prompt. On macOS or Linux, use Terminal with Bash. The script performs the renames sequentially and reports each change, so you can watch it execute in real time. If something goes wrong, the original filenames are visible in the script output for manual recovery.
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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