A fingerprint, a timestamp, forever.
Thappa never needs your work to be public. It turns your content into a one-way fingerprint, anchors that fingerprint on a public blockchain, and hands you a certificate anyone can check.
Hash — a fingerprint of the exact bytes
Your file or text is run through keccak256, producing a 32-byte hash unique to those exact bytes. Change a single character and the hash changes completely. The hash reveals nothing about the content — so you can prove authorship of a private paper or idea without disclosing it.
Pin to IPFS — content-addressed storage
If you choose to store the work, the file (or just its metadata) is pinned to IPFS, where it's addressed by its own content. The resulting CID becomes part of the seal, so the record points at the exact artifact.
Mint the seal — on Polygon, duplicate-proof
The SealD registry contract mints a seal storing the owner address, the content hash, the content type, and the block timestamp. The contract is non-upgradeable, and a given hash can be sealed exactly once — so a seal is unambiguous proof of who sealed that work first.
Get your proof — a stamped certificate
You receive a certificate and a public verification link. PDFs come back visibly stamped with the seal number, hash, and timestamp. Nothing about the record can ever be altered — not by you, not by us.
Seal openly, or keep the work private and publish only the hash.
The seal belongs to your address; export or verify it anywhere.
No account needed — verification reads straight from the chain.