Proofisy

Can I cancel anytime?

Yes. You can cancel your subscription anytime. Your subscription will remain active until the end of the current billing period.

Which file types are supported?

Any file type can be fingerprinted and verified: images, videos, PDFs, ZIP archives, contracts and more.

Are my files uploaded to Proofisy?

No. All fingerprint generation and verification are performed locally in your browser.

Can Proofisy tell me what was modified in a file?

No. Proofisy uses cryptographic hashing to determine whether a file is identical to its reference version. It can detect that a difference exists, but it cannot identify which content was modified, added, or removed.

What should I do if a file fails integrity verification?

Proofisy only confirms that the current file differs from the original reference file used to generate the proof.

Proofisy cannot determine what was changed, when the change occurred, or who made the changes.

However, depending on your situation, the following actions may help:

• Carefully inspect the document to identify any visible changes. The modification may be minor (such as metadata or formatting changes) or significant (such as altered content).
• If you have stored a trusted copy of the original document elsewhere, compare it with the current file to identify the differences.
• Verify whether the detected changes were expected, authorized, or the result of a normal document update.
• If the file should not have changed, consider restoring a trusted backup or retrieving a known authentic version.
• If the modifications are legitimate and the current version is now the approved version, generate a new proof for this updated file.

A failed integrity verification does not necessarily indicate malicious tampering. It simply means that the current file is not strictly identical to the file that was originally used to generate the proof.