chrome extension

deny.sh in your browser.

Try real-and-decoy encryption locally on a test credential selected in your Chromium browser. Install the free unpacked extension using the steps below.

↓
→

Right-click encrypt

Select any text on any page, right-click, and encrypt it with two passwords. Ciphertext copies to your clipboard.

▢

Popup mode

Click the extension icon for a full encrypt, decrypt, and vault interface without leaving your current tab.

📄

File protection

Drag and drop any file into the popup to encrypt it locally. Download the encrypted output directly.

How it works

1

Install

Load the unpacked build; the Chrome Web Store listing is not yet available. Works in Chrome, Edge, Brave, and any Chromium browser.

2

Select text

Highlight any text on any page. Right-click and choose "Encrypt with deny.sh".

3

Encrypt

Set two passwords and write a harmless alternative (decoy). It creates encrypted data (ciphertext) and two control files that select the real or decoy message. Same two passwords decrypt either way; the control file you supply chooses which plaintext you get back.

Technical details

Standard
Manifest V3
Isolation
Isolated interface (Shadow DOM)
Crypto
Browser encryption (WebCrypto) + password-to-key derivation (Argon2id)
Storage
chrome.storage.local, never synced
Network
Zero outbound requests
Size
Self-contained build with bundled password-to-key code

This extension makes zero network requests. Your text, passwords, and files never leave your browser. All cryptographic operations run in the extension's isolated context using the browser's built-in WebCrypto API.

Supported browsers

Any browser with Manifest V3 support.

Chrome Edge Brave Arc Chromium Opera

Get it

The Chrome Web Store listing is not yet available. An API key is for hosted services, not an extension download; local encryption does not need one.

Explore hosted services
Limits and scope

What to know before production.

The extension currently uses manual developer installation. A Chrome Web Store listing is not yet available; local encryption does not need an API key.

Review evidence and current status ↗ · Threat model