The file is read in browser memory and a new output is created without overwriting the original.
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Code & file security
Local File Risk Pre-Scan
Inspects filename, size, magic bytes, MIME consistency, and risky text patterns in-browser without executing or uploading the file. It is not antivirus and cannot conclusively detect or clear new, packed, or complex malware.
✓ Free✓ No account✓ In-browser
QUICK ANSWER
What does this tool do?
Inspect extension, signature, double extension, macro indicators, and bounded content samples without uploading.
Result
Your result will appear here.
APPLICATION AND DECISION GUIDE
Local File Risk Pre-Scan: method and usage
Inspects filename, size, magic bytes, MIME consistency, and risky text patterns in-browser without executing or uploading the file. It is not antivirus and cannot conclusively detect or clear new, packed, or complex malware.
local file or files of a supported type within the disclosed size limit Confirm the shape first with a small example containing no personal data.
a downloadable new file, size and format metrics, and disclosed processing limits
Practical steps
- Choose only a file you are authorized to inspect.
- Run the size-bounded local scan; the file is never opened or executed.
- If findings are suspicious, isolate the file and verify with a current professional security product.
preserving the original and checking that output opens correctly, retains expected pages or frames, size, and visible quality
Code is not executed, and no finding does not prove the absence of vulnerabilities.
Suitable use cases
- Initial triage of a downloaded file
- Extension/signature mismatch checks
- Macro and script indicator search
LEARN THE WORKFLOW
Guides for this tool
PWA Installation and Offline Caching: A Privacy-First Design Guide
Understand web app installation, the service worker lifecycle, and cache boundaries that keep sensitive inputs out of persistent storage.
Read guide →Browser File Risk Scanning: Magic Bytes, Double Extensions, and Real Limits
Inspect extension, signature, macro, and bounded content signals without executing a file—and do not confuse triage with antivirus verification.
Read guide →ABOUT THIS TOOL
Frequently asked questions
What input does Local File Risk Pre-Scan accept?+
local file or files of a supported type within the disclosed size limit Choose only a file you are authorized to inspect.
What does Local File Risk Pre-Scan return?+
a downloadable new file, size and format metrics, and disclosed processing limits The file is read in browser memory and a new output is created without overwriting the original.
How should I validate Local File Risk Pre-Scan output?+
preserving the original and checking that output opens correctly, retains expected pages or frames, size, and visible quality
Does Local File Risk Pre-Scan send or store input on a server?+
Tool input is processed in the active tab. Saving to the Workstation or transferring to another tool is a separate choice. Consider browser extensions and shared devices separately; the privacy page explains advertising and network connections.