Seal PDFs with an API that just works.
seal.club is a document sealing API for builders who need cryptographic integrity without weeks of integration. Ship tamper-evident PDFs in minutes, not sprints.
import { Seal } from '@sealclub/sdk';
const seal = new Seal({ apiKey: process.env.SEALCLUB_API_KEY });
await seal.document.submit(pdfBuffer);
// Tamper-evident seal + receipt in one callIllustrative example — final SDK surface ships with your account.
Built for teams who care about document integrity
Everything you need to seal at scale
Clear API, strong defaults, and documentation you can actually skim on a Friday afternoon.
Cryptographic sealing
Apply standards-aware seals so every PDF proves it has not been altered since issuance.
Documentation first
Guides, examples, and error messages that tell you what to do next — not just what went wrong.
One-line integration
Start in a single import. No weeks-long professional services engagement required to ship.
Trust, but verify — automatically
Whether you are closing loans, issuing certificates, or archiving contracts, your users deserve proof that files are authentic. seal.club automates that proof so your team can focus on the product around it.
- Audit-friendly receipts and verification hooks
- Designed for CI-friendly test keys
- Security posture documented openly
Ready to seal your next document?
Check pricing and docs, grab your API key when you are ready, and ship your first sealed PDF — free tier included.