Question 1

Why should I verify a Chaindoc document?

Accepted Answer

Verification proves that the file you're looking at is the exact version that was notarised in Chaindoc. Compliance teams, procurement managers, and legal reviewers use this to confirm contracts and certificates haven't been modified after signing. If you're handing a document off to a third party, running the check first keeps your audit trail intact and gives the recipient confidence that what they're reading is authoritative.

Question 2

How does the verification process work?

Accepted Answer

Everything happens in your browser. Chaindoc streams the document, computes a keccak256 hash, and compares it against the hash in the uploaded certificate. The API then checks both values against the immutable blockchain ledger and returns a verdict: valid if all three match, invalid otherwise. The whole thing takes a few seconds.

Question 3

Does Chaindoc store my document when I verify it?

Accepted Answer

No. The document never leaves your browser. Only the computed hash, file metadata, and a one-time token are sent to the backend over TLS. Because Chaindoc already hosts the certificate, it can validate your request without persisting the uploaded file.

Question 4

Who can see the verification results?

Accepted Answer

Every attempt (successful or failed) is logged in the certificate timeline. The log records who initiated the check, the timestamp, the IP region, and the outcome. Team members with certificate access can review and export the timeline for auditors.

Question 5

What cryptography secures the verification?

Accepted Answer

Chaindoc signs responses with an Ed25519 key pair. Document hashes are anchored to an Ethereum-compatible chain, so anyone can independently check the anchor transaction. Transport is protected with TLS, and a rolling key-rotation policy keeps signing keys short-lived. The eIDAS regulation recognises advanced electronic signatures backed by this kind of cryptographic assurance.

Question 6

What happens if the hashes don't match?

Accepted Answer

The interface shows which part failed (document hash, certificate hash, or both) and marks the attempt as invalid. Common causes: uploading a draft instead of the final version, editing the file after signing, or using the wrong certificate. Re-run the check with the correct files. The failed attempt stays in the timeline so your team knows a mismatch occurred.

Question 7

Can I verify the same document again later?

Accepted Answer

Yes. Run the check whenever you retrieve the file from storage, before sharing it, or as part of routine compliance reviews. If you need to automate this, the Chaindoc API has an endpoint for programmatic checks. Every run adds to the history so future reviewers can see the entire chain.

Verify document authenticity