LetsSeal

Seal and verify bank & lending documents

Statements, loan and mortgage agreements, KYC packs, and guarantees that carry their own proof, so a lender, a landlord, or a counterparty can confirm a document is genuine in seconds. A doctored statement or a forged bank letter fails on sight.

For banks, lenders, fintechs, and building societies.

Open the app Developer docs
What a seal proves

Four guarantees, in banking & lending

A statement that can't be doctored

A changed balance, transaction, or name fails verification. The edited-bank-statement problem, closed at the source.

The issuing bank or lender, named

Every statement and agreement names the institution that sealed it, chaining to a published root, a specific certificate, not a letterhead anyone can copy.

Fixed at the moment of issue

Statement periods and agreement dates are timestamped on the blockchain, decisive for affordability checks, drawdown, and disputes over which version was current.

Verified without a callback

A landlord, a broker, or another bank confirms a document at a permalink, instantly, and free, with no call to your fraud desk.

How it works

From your file to a proof anyone can check

The same pipeline every time. The seal and the timestamp travel with the file, so the proof is self-contained.

Your file
Your signed PDF
Seal
Signed over every byte · PAdES
Anchor
Blockchain timestamp + public transparency log
Proof page
A permanent /d/… link travels with the file
Anyone verifies
Free, public, offline-capable, for anyone
The proof travels inside the file. Verification stands on the published root, the transparency log, and the blockchain, so a court, a bank, or a counterparty can check it independently, forever.
Step by step · the web app

Seal it in the app, no setup

  1. 1

    Sign in as your institution

    Open app.letsseal.org and sign in. Your organisation gets its own certificate authority the first time you seal. Every document you issue chains to it.

  2. 2

    Upload or generate the document

    Drop in the statement, agreement, or letter. It's sealed with your certificate as a PAdES signature over the whole file, so any later edit is caught.

  3. 3

    Anchored and logged automatically

    The fingerprint is timestamped on the blockchain and written to the public transparency log. The customer gets a normal PDF that also verifies.

  4. 4

    Deliver with a proof link

    Every document has a permanent proof page. Whoever relies on it, a lender, a letting agent, opens the link to confirm it's genuine and unaltered.

Step by step · the CLI

Automate it from your terminal or CI

The sealbot CLI does the same thing, scriptably, one command per file, straight into your pipeline.

# Seal every statement in a run as it's generated
$ sealbot watch /srv/statements --mode seal --org examples
watching /srv/statements … sealing new & changed PDFs (idempotent)

# Seal a single loan agreement under your institution
$ sealbot seal mortgage-offer.pdf --org examples
sealed   mortgage-offer.pdf
  proof  https://letsseal.org/d/9d10af…7c22

# A third party confirms a statement, public, no account
$ sealbot verify statement-2026-06.pdf
✓ authentic · unaltered · sealed by Let's Seal Examples

Point a watched folder or your statement-generation pipeline at Let's Seal and every document leaves already sealed, timestamped, and carrying a proof link, one command per file, no per-seal fee.

Full CLI & API reference
See it in action

What a proof looks like, and what you can seal

Issuer verified, controls letsseal.org
Authentic & unaltered
Document
A sealed bank statement
Issuer
Let’s Seal Examplesletsseal.org
SHA-256
64-hex fingerprint ✓

Anchored on the blockchain

Recorded in the public transparency log

Public and free to verify, by anyone, with standard tools.
Open the live proof

A single use case, many documents. Each of these is sealed the same way:

  • A sealed bank statement

    Live proof

    Open the proof page the way a lender or landlord would: it shows the statement is authentic, unaltered since issue, sealed by the named bank, and timestamped on the blockchain, no callback required.

  • A mortgage or loan agreement

    Seal the executed offer or agreement so a broker, solicitor, or borrower can confirm the terms are exactly as issued. An altered rate or amount is caught instantly.

  • A KYC or onboarding pack

    Seal the verified onboarding documents so a downstream institution can confirm the pack is the one you produced, unaltered, provable customer due diligence.

  • A guarantee or letter of credit

    High-value instruments sealed and timestamped on issue, so a beneficiary can verify authenticity before relying on them.

Live proofs are real documents sealed under the “Let’s Seal Examples” organisation.

Common documents

What you’ll seal

  • Bank statements
  • Loan & mortgage agreements
  • KYC / onboarding documents
  • Letters of credit
  • Guarantees
  • Reference & confirmation letters
Questions

Straight answers

Does this stop fake bank statements?
A sealed statement can't be edited without failing verification, and anyone can check it against the proof link. The doctored-PDF version simply won't verify as issued by you, which is exactly the fraud a rental or lending check is trying to catch.
Can a third party verify without an account?
Yes. Verification is public and free. A landlord or another bank opens the proof link, or drops the PDF into the verifier. The proof carries everything they need.
Can I seal every statement automatically?
Yes. Point the CLI or a watched folder at your statement pipeline and every document leaves sealed, timestamped, and carrying a proof link, one command per file, no per-seal fee.
Does the customer need special software?
No. They get a normal PDF that opens anywhere, and it also verifies against the public portal and any standard PAdES validator.

Start sealing banking & lending documents

Free and open. Seal in the app, automate from the CLI, and hand anyone a proof they can verify themselves.

Open the app All use cases