security first

Your data stays private, even from us.

Most ERPs protect data in transit and trust the server with the rest. LetterSheets encrypts your most sensitive records in your browser and keeps the keys with you.

E2EClient-side
ML-KEM-768Key exchange
ML-DSA-65Signatures
0Vendor backdoors

Zero-knowledge by design

Employee PII, payroll figures, and financial records are encrypted client-side. The server stores ciphertext it cannot read — a breach exposes nothing usable.

Quantum-safe cryptography

Key exchange and signatures use NIST post-quantum standards, so data captured today can't be decrypted by future quantum machines.

ML-KEM-768 · ML-DSA-65

You hold the recovery key

Each company gets a downloadable recovery key at setup. Access is unlockable only by you — no silent backdoor, no vendor master key.

Secure from the first login.

Encryption isn't a setting you switch on — it's how the platform works from the moment you create a company.

01

Create your company

Spin up an encrypted workspace and download your recovery key — the only path back into your data.

02

Unlock with your password

Your password derives the key that decrypts sensitive fields, right in the browser. The server never sees it.

03

Work as usual

Records encrypt and decrypt transparently as you use the app — nothing to manage, nothing exposed.

What the server can and can't see.

Encrypted & private

  • Employee personal information
  • Salaries and payroll figures
  • Sensitive financial amounts
  • Your encryption keys and password

Operational metadata

  • Record structure and timestamps
  • Which company a record belongs to
  • Non-sensitive reference fields
  • What's needed to route and store data

Run your business on encryption you control.

Bring HR, accounting, inventory, and the rest onto one private, quantum-safe platform.