Source Map Unpacker
Extract all original source files from a .map file and download them as a ZIP archive.
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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.
Use cases
Debugging production code
"Extract the original TypeScript or ES6+ source from a minified JavaScript bundle's source map to debug production issues."
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."
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."
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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.