JavaScript Source Map Exposure Checker
Paste HTML or headers to flag source map references such as .map files and sourceMappingURL comments.
Runs in your browser. Nothing is uploaded — your input is processed on this device and discarded when you close the tab.
JavaScript Source Map Exposure Checker
How to use this tool
- Enter your values in the fields above.
- Press Generate to see the result.
- Use Load sample to try the worked example, Copy result to copy it, or Clear to start again.
Worked example
Pasted HTML containing sourceMappingURL=app.js.map flags one exposed map reference, app.js.map.
What this tool does not do / Limits
This tool only analyses HTML or headers you paste here. It never contacts, scans or verifies a live site, and a clean paste does not prove a site has no exposed maps.
Frequently asked questions
Does this check my live website?
No. Paste the HTML or headers yourself; the tool never contacts any site.
What counts as exposed?
Any .map file name or sourceMappingURL comment found in the pasted text.
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