Source Map Unpacker
Extract all original source files from a .map file and download them as a ZIP archive.
Source Map Unpacker is a free, browser-based online tool that lets you extract all original source files from a .map file and download them as a zip archive with complete privacy and security. All processing happens directly on your device — no files are uploaded to any server. Whether you are working with professional documents, personal files, or sensitive data, this tool provides a fast and reliable solution without requiring any software installation or account creation.
How to use
Upload your source map
Drag and drop a .map file onto the drop zone, or click to browse your files. The tool accepts .map and .json files.
Automatic extraction
The tool parses the source map JSON, reads all sources and sourcesContent entries, and packages them into a ZIP archive preserving the original directory structure.
Download the ZIP
Once processing is complete, click the download button to save the ZIP file containing all extracted source files.
Complete Guide to Source Map Unpacker
Worked Examples
Example: Basic Source Map Unpacker Usage
Given: A user needs to extract all original source files from a .map file and download them as a zip archive for a work project.
Step 1: Open the Source Map Unpacker tool in your web browser.
Step 2: Upload or enter your input data as instructed by the tool interface.
Step 3: Configure any available settings to match your requirements.
Step 4: Click the process/generate button and wait for the result.
Result: The tool processes your input locally in your browser and produces the desired output, ready to download or copy.
Example: Professional Source Map Unpacker Workflow
Given: A professional working with multiple files needs efficient batch processing.
Step 1: Prepare all input files in the correct format.
Step 2: Process each file through the tool one at a time.
Step 3: Verify each output meets quality standards before proceeding.
Result: All files are processed with consistent quality, maintaining privacy since no data leaves the browser.
Use cases
Debugging production code
“Extract the original TypeScript or ES6+ source from a minified JavaScript bundle's source map to debug production issues. This is a common use case that professionals, students, and everyday users encounter regularly. The tool handles this task efficiently in your browser, ensuring your data remains private and the process is completed in seconds without any software installation.”
Recovering lost source code
“If you have a source map but lost the original source files, use this tool to recover the complete source tree. This is a common use case that professionals, students, and everyday users encounter regularly. The tool handles this task efficiently in your browser, ensuring your data remains private and the process is completed in seconds without any software installation.”
Auditing third-party libraries
“Inspect the original source code of third-party libraries by extracting their source maps to understand what the minified code does. This is a common use case that professionals, students, and everyday users encounter regularly. The tool handles this task efficiently in your browser, ensuring your data remains private and the process is completed in seconds without any software installation.”
Frequently Asked Questions
?What is a source map?
A source map is a JSON file (usually with a .map extension) that maps minified or transpiled code back to its original source. It contains the original file names and their contents.
?What file formats are supported?
The tool accepts .map and .json files that follow the Source Map v3 specification. These are typically generated by bundlers like Webpack, Vite, Rollup, or esbuild.
?What if the source map has no sourcesContent?
Some source maps only contain file paths (sources) without the actual content (sourcesContent). In that case, the tool cannot extract files and will show an error message.
?Does this tool handle webpack:// URLs?
Yes. The tool automatically strips common protocol prefixes like webpack:// from file paths, producing clean directory structures in the output ZIP.
?Is my data private?
Yes. Everything runs entirely in your browser. No data is uploaded to any server. Your source maps and extracted files never leave your device.
?Is this tool free?
Yes. Completely free with no limits, no sign-up required.
?Can I use this with CSS source maps?
Absolutely. CSS source maps generated by SASS, LESS, PostCSS, or CSS minifiers follow the same format and work perfectly with this tool.
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