Post-Quantum Messaging · ML-KEM · NIST FIPS-203

Encrypted messages
quantum computers
cannot read

Send text and files with ML-KEM + AES-256-GCM encryption — directly in your browser. Get a shortlink. Paste it anywhere. The server never sees your content.

🔒 Encrypt a message now Create free account →
How it works

Three steps. No installation.

Everything happens in your browser. The server only stores encrypted data it cannot read.

🔑 Get keysGenerate ML-KEM keypair
→
✍️ WriteText or file attachment
→
🔒 EncryptML-KEM + AES-256-GCM in browser
→
🔗 Sharepqcserver.com/m/xxx
→
🔓 DecryptRecipient's browser only
Sender
1. Visit /encrypt.html — no login required
2. Enter the recipient's username or paste their ML-KEM public key
3. Type your message and optionally attach a file
4. Click Encrypt — everything happens in the browser
5. Copy the shortlink and paste it wherever you want
Recipient
1. Click the shortlink received via email, chat or SMS
2. The page loads the encrypted data from the server
3. Paste your ML-KEM private key in the field shown
4. Decryption happens in the browser — server sees nothing
5. Read message and download file (if any)
Features

Everything you need

🔥
Burn After Read

Enable burn-after-read to have the message permanently deleted from our server the moment the recipient opens it. Combined with TTL, messages never linger.

📎
File Attachments — Any Size

Attach files of any size using GridFS chunked upload. Files are encrypted in the browser before upload. 3MB chunks — well under Cloudflare's 100MB per-request limit.

👤
Public Profiles

Register a username and share pqcserver.com/u/yourname. Anyone can send you an encrypted message without knowing your key in advance — just your username.

🔌
Embeddable Widget

Add a "Send encrypted" button to any website with one line of HTML. The modal opens inline — users never leave your site. Supports username lookup, manual key paste, or no configuration.

Widget Integration

One line. Any website.

Add post-quantum encryption to onionmail.org, your website, or any web application.

Known recipient:

<script src="https://pqcserver.com/assets/widget.js"
        data-recipient="alice_smith"></script>

Widget auto-loads Alice's public key and opens at Step 2 (message).

Unknown recipient — user picks:

<script src="https://pqcserver.com/assets/widget.js"></script>

Step 1 shows username lookup + manual key paste. Perfect for email clients.

The modal guides users through 3 steps:

1
Recipient — username lookup or paste public key
2
Message — text + optional file attachment
3
Done — copy shortlink, paste anywhere
Comparison

PQCServer vs PGP

Why post-quantum matters — and why the user experience matters equally.

Feature PGP (RSA/ECC) PQCServer (ML-KEM)
Quantum resistance ✗ Broken by Shor's algorithm ✓ ML-KEM lattice-based
Installation required ✗ Plugin or desktop app ✓ Browser only, no install
Sharing mechanism Copy/paste armored blocks ✓ Simple shortlink
File attachments Limited by email clients ✓ Any size via GridFS
Key discovery Manual key exchange ✓ Username lookup
NIST 2024 standard ✗ Legacy standards ✓ FIPS-203 / FIPS-204
Embeddable ✗ Standalone only ✓ One-line widget
Start encrypting in 30 seconds

No installation. No credit card. Generate your post-quantum keypair now.

🔑 Generate my keys 🔒 Encrypt a message Create account →