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Are my files uploaded?
Files stay in this browser. Hashes and signatures verify byte integrity, not legal identity or authorship.
What can this operation prove?
Comparison detects different bytes, not which file is original. A valid signature requires independently trusting its public key. A drawn or visual signature is not a cryptographic signature.
What should I check before sharing the result?
The private key is non-exportable and exists only on this page. It is never stored or uploaded. Clearing or leaving this page destroys access; generated signatures remain verifiable with their exported public key.
How to use File Authenticity & Signature Checker
Select Files
Add your file or drag & drop
Process Locally
Processed in your browser
Download Result
Get your result in seconds
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