How to Change Multiple File Extensions at Once on Windows 11 Easily

Have you ever had a folder full of files with the wrong extension? Maybe you downloaded images as .jpeg but need them in .jpg, or you have dozens of .txt files that should be .csv. Renaming each file manually would take forever.

The good news? Windows 11 makes it possible to change multiple file extensions at once using different methods—some simple and some advanced. In this guide, we’ll walk you through step-by-step solutions that will save you time and frustration.

📝 Key Takeaways

• Windows 11 doesn’t allow batch renaming extensions directly via File Explorer, but there are workarounds.

• You can rename multiple file extensions using:

  • File Explorer (for visible extensions)

  • Command Prompt (bulk rename with commands)

  • PowerShell (more advanced batch renaming)

  • Third-party tools (easy GUI-based solutions)

• Always back up files before batch renaming to avoid mistakes.

Why Change Multiple File Extensions at Once?

There are several common reasons:

• 📂 File organization – standardize file formats.

• 🎵 Media conversion – e.g., rename .m4a files to .mp3.

• 📊 Data handling – switch .txt to .csv for spreadsheets.

• 🛠 Compatibility – some software requires specific extensions.

Preparations Before Changing File Extensions

Before you start:

1. Enable File Extensions in Explorer

   • Open File Explorer → click View > Show > File name extensions.

   • Now, all file extensions (like .jpg, .txt) will be visible.

2. Back Up Your Files

   • Mistakes can break file associations. Copy your files to a backup folder first.

Method 1: Change Multiple File Extensions Using File Explorer

This method works when you only have a few files.

1. Select all files in a folder (Ctrl + A or hold Shift + click).

2. Right-click and choose Rename.

3. Change the extension of one file (e.g., from .txt to .csv).

4. Windows will ask:

   “If you change a file name extension, the file might become unusable. Are you sure you want to change it?”
   Click Yes.

5. All selected files will now have the new extension.

👉 Limitation: This only works if all files share the same extension.

Method 2: Change File Extensions with Command Prompt

For bulk renaming, Command Prompt is powerful.

1. Press Win + R, type cmd, and hit Enter.

2. Navigate to your folder using:

   cd "C:\path\to\your\folder"


3. Run this command to change all .txt files to .csv:

   ren *.txt *.csv


👉 Example: All report1.txt, report2.txt, report3.txt become .csv.

Method 3: Change File Extensions Using PowerShell

PowerShell offers more flexibility.

1. Open PowerShell as Administrator.

2. Navigate to your folder:

   cd "C:\path\to\your\folder"


3. Run this script to rename .jpeg to .jpg:

   Dir *.jpeg | Rename-Item -NewName { $_.name -replace '.jpeg','.jpg' }


👉 You can modify the script for different extensions (e.g., .log → .txt).

Method 4: Use a Third-Party Tool (Beginner-Friendly)

If you don’t like commands, third-party tools make it easier:

• Bulk Rename Utility (free, powerful, but advanced interface)

• Advanced Renamer (user-friendly batch renaming)

• File Renamer Basic

These tools let you:

• Change extensions in bulk.

• Add prefixes/suffixes.

• Apply advanced renaming rules.

Comparison of Methods

Best Practices When Renaming File Extensions

• ✅ Always back up files before batch operations.

• ✅ Make sure the file content matches the extension (renaming doesn’t convert the file format).

• ✅ Test renaming on a few files before doing a full batch.

• ✅ Use third-party tools if you want more options like numbering or pattern renaming.

Conclusion

Renaming multiple file extensions at once in Windows 11 can be done in several ways:

• File Explorer – easiest for small jobs.

• Command Prompt or PowerShell – powerful for automation.

• Third-party tools – best for beginners or complex tasks.

By following these steps, you can quickly standardize file types and save hours of manual renaming.

❓ FAQs About Changing Multiple File Extensions

1. Does renaming a file extension change its format?

No. It only changes the name. The file’s content and structure stay the same.

2. Can I rename files with different extensions at once?

Yes, but you’ll need PowerShell or a third-party tool for mixed extensions.

3. Is it safe to change file extensions?

Yes, but if the program doesn’t support the new extension, the file may not open.

4. What’s the fastest method for bulk renaming?

Command Prompt (ren *.ext1 *.ext2) is the quickest built-in method.

5. Which tool is best for beginners?

Advanced Renamer is user-friendly, while Bulk Rename Utility is more advanced.