Document & Markup Converter
About File Extension Changer
The Batch File Extension Changer & Script Builder changes file extensions across lists of filenames (e.g. `.jpeg` to `.jpg`, `.htm` to `.html`, `.ts` to `.js`), providing live collision checks and terminal batch scripts.
How to Use File Extension Changer
Step 1
Paste your filenames or list of paths.
Step 2
Enter your desired new file extension (e.g. `jpg` or `webp`).
Step 3
Review the updated filenames in the preview column.
Step 4
Copy the generated terminal script or renamed list.
Practical Use Cases for File Extension Changer
Standardizing Media & Web File Extensions
Batch rename `.jpeg` files to standard `.jpg` or `.yaml` to `.yml` across an entire code repository.
Converting TypeScript to JavaScript File Lists
Generate terminal migration scripts to rename compiled `.ts` extensions to `.js` without altering base filenames.
Input & Output Examples
Changing `.htm` to `.html`
Files: `index.htm`, `about.htm` | Target Extension: `html`
Preview: `index.html`, `about.html` | PowerShell: `Get-ChildItem *.htm | Rename-Item -NewName { $_.name -replace '\.htm$','.html' }`Key Features & Performance
- ✓Changes extension while preserving multi-part extensions (e.g. `.tar.gz`).
- ✓Generates copy-pasteable Bash and PowerShell terminal commands.
- ✓Collisions and invalid extension alert detection.
- ✓100% Client-Side memory execution.
- ✓1-Click Copy terminal script.
Key Terminology & Definitions
File Extension
A suffix separated by a period at the end of a computer file name indicating the encoding or usage format of the file.
Compound Extension
A file extension consisting of multiple dot-separated components representing layered packaging (e.g. `.tar.gz` or `.d.ts`).