01 / DOCUMENT INTEGRITY

Prove a document has not changed.Spot the ones that have.

LudeProof registers a cryptographic fingerprint and a trusted timestamp for any file, so you can prove it existed and prove it never changed. And when a document lands on your desk, a forensic signals report tells you what its metadata, structure and signatures actually say.

Start with a 14 day Pro trialVerify a document

RFC 3161 trusted timestamps live

02 / HOW IT WORKS

Two jobs, done honestly

PROTECT

The digital notary

Upload a contract, invoice, report or photo. We compute its SHA 256 fingerprint, anchor it with an independent RFC 3161 trusted timestamp, and issue a certificate with a public verification link and QR code. Re upload the file any time: if a single byte changed, we tell you. The document itself is discarded after processing. We keep only the fingerprint.

INSPECT

The signals report

Received a PDF, image or Word file you do not fully trust? The signals engine reads its metadata, revision history, tool chain, embedded signatures and structure, then reports every observation in plain English with a risk score. Evidence and observations, never a fake stamp of authenticity.

03 / WHAT WE CHECK

The signals engine

Revision history

PDFs keep a trail of every save. We count the revisions and flag documents that were resaved after creation.

Metadata forensics

Creation and modification dates, authoring tools, authors and edit history, cross checked for contradictions.

Digital signatures

We detect embedded PAdES and Adobe signatures, the strongest integrity evidence a document can carry.

Tool chain analysis

A bank statement produced by image editing software is worth knowing about. We surface the full tool chain.

File type honesty

A PDF renamed to look like a photo, or the reverse, is a strong deception signal. Content is checked against the name.

Content credentials

Files carrying C2PA content credentials are detected, the emerging standard for provenance and AI disclosure.

04 / THE HONEST PART

What we will never claim

No tool can look at an arbitrary file and certify it is genuine. Anyone who says otherwise is selling you confidence, not evidence. LudeProof reports what can actually be established: whether a registered document changed, what a file's own metadata and structure reveal, and whether its cryptographic signatures hold. You get evidence, clearly explained, and you stay the judge.

05 / FOR BUILDERS

One API call per answer

Everything in the dashboard is available over a simple REST API with bearer keys, on the Business plan. Notarize, verify and inspect from your own product or back office.

curl -X POST https://ludeproof.com/api/v1/check \
  -H "Authorization: Bearer lp_live_..." \
  -F "[email protected]"
Read the API documentation