Verify Digital Evidence Integrity Online

No. All cryptographic verification (signature checking, hash computation) happens entirely in your browser using the Web Crypto API. Your ZIP file is never uploaded anywhere. The only external calls are to verify timestamps: the OpenTimestamps API and the eIDAS TSA verification endpoint.

• Manifest signature: Verifies the RSA-2048 digital signature on manifest.json using the included public key.
• File integrity: Computes SHA-256 hashes for each evidence file and compares them against the manifest.
• Forensic log: Validates the tamper-evident hash chain and cross-references with the chain of custody document.
• Device integrity: Reports the device integrity score and any automation indicators.
• Blockchain timestamp: Verifies the OpenTimestamps proof against the Bitcoin blockchain (if present).
• EU eIDAS timestamp: Verifies the qualified electronic timestamp against the TSA (if present).

No. The Trust Verifier is completely free and requires no account, login, or subscription. Anyone can independently verify a ProofSnap evidence package — opposing counsel, judges, insurers, or law enforcement.

Under EU Regulation No 910/2014 (eIDAS), a qualified electronic timestamp carries a legal presumption of accuracy of the date and time it indicates. It is issued by a qualified Trust Service Provider (TSP) listed on the EU Trusted List. ProofSnap uses Disig a.s., an EU-accredited TSP, for eIDAS-compliant timestamps. Available on the Enterprise plan.

Yes. Every ProofSnap evidence package is designed for independent verification using standard tools:

• Signature: openssl dgst -sha256 -verify publickey.pem -signature manifest.sig manifest.json
• Hashes: sha256sum screenshot.jpeg and compare with manifest.json
• Blockchain: Upload manifest.json.ots to opentimestamps.org
• eIDAS: openssl ts -verify -in manifest.json.tsr -data manifest.json -CAfile disig-root.pem

Yes, but only when properly authenticated. Under FRE 901/902 (US Federal Rules of Evidence), digital evidence must be authenticated to prove it is what its proponent claims it to be. Plain screenshots can be challenged as manipulated. ProofSnap solves this by capturing screenshots with SHA-256 hash fingerprints, RSA-2048 digital signatures, and blockchain timestamps — creating a verifiable, tamper-evident chain of custody that meets FRE 902(13)-(14) self-authentication standards. In the EU, evidence with an eIDAS qualified timestamp enjoys a legal presumption of integrity under Regulation 910/2014.

The verifier uses three independent tamper-detection mechanisms. First, it computes a SHA-256 hash for each file and compares it to the hash recorded in the manifest at capture time — if even a single bit has changed, the hash will be completely different. Second, it verifies the RSA-2048 digital signature on the manifest, which proves the manifest was created by ProofSnap and has not been modified. Third, it validates the forensic log's tamper-evident hash chain, where each event is cryptographically linked to the previous one — any insertion, deletion, or modification breaks the chain.

Required files:

• screenshot.jpeg — full-page capture of the web page
• metadata.json — URL, timestamps, browser info, TLS details
• page.html — complete HTML source of the page
• evidence.pdf — formatted evidence report
• domtextcontent.txt — extracted text content
• manifest.json — SHA-256 hashes of all files
• manifest.sig — RSA-2048 digital signature
• publickey.pem — public key for signature verification

Optional files:

• forensic_log.json — tamper-evident event log
• chain_of_custody.json — ISO 27037 chain of custody
• manifest.json.ots — OpenTimestamps blockchain proof
• manifest.json.tsr — eIDAS qualified timestamp (Enterprise)
• eidas_validation.json — long-term validation data (Enterprise)