How it works
Three steps from PDF to proof.
BlockSign sits in front of Solana so your signers don't have to. They click a link, sign in the browser, and walk away — the on-chain commitment happens behind the scenes, in under a second.
Step 01
Upload your PDF
Drop a contract, NDA, or offer letter. We compute the SHA-256 server-side and store the file behind row-level access — the content never reaches our analytics.
Step 02
Send to signers
Add signer emails. Each signer gets a single-use, token-gated link — they click, sign in the browser, done. No wallet, no signup, no SOL needed.
Step 03
Commit & verify
Each signed version emits a Solana memo carrying the document's stamp. Anyone holding the PDF can verify it against chain state, with or without a BlockSign account.