Zero-Knowledge Browser Encrypted Vault, Universal Text Converter & Writing Analytics
In an era dominated by centralized cloud services and remote database leaks, true privacy requires keeping your sensitive data on your own hardware. Notes Encrypted Vault provides an uncompromising, browser-native sanctuary for your personal thoughts, credentials, journal entries, and sensitive documentation while doubling as an advanced Text-to-PDF, Text-to-Word, and Multi-Format Document Exporter.
Unlike conventional web applications that pass passwords and text content to remote servers, this tool operates on a strict Zero-Knowledge Trust Model. Your master password is never transmitted, stored in cookies, or written to browser disk storage. Every single cryptographic operation — from key derivation to payload encryption and decryption — executes isolated inside your device's browser execution context using the high-performance Web Crypto API (`window.crypto.subtle`).
Client-Side Universal Text Conversion Engine
In addition to zero-knowledge military-grade encryption, Notes Encrypted Vault serves as an all-in-one client-side Text Converter. Convert raw text or Markdown notes into 8 universal document formats directly inside your browser without uploading data to external conversion servers:
Convert plain text, Markdown, callouts, and tables directly into publication-ready PDF documents via your browser's native PDF print engine.
Export formatted drafts into Microsoft Word `.doc` or universal Rich Text `.rtf` files compatible with WordPad, TextEdit, and desktop office suites.
Export raw notes as portable `.md` files for Obsidian, Logseq, and VS Code, or structured `.txt` files for universal reading on any system.
Export structured data to `.csv` spreadsheets for Excel & Google Sheets, standalone `.html` web pages, or structured `.json` data blobs.
Writing Analytics: Word Counter & Speech Time Estimator
Stay in complete control of your document length and presentation preparation with our real-time Writing Analytics Engine:
Instant word count and dual character counts (total characters vs. characters excluding spaces) for strict length limits.
Deep structural breakdown measuring total sentences, paragraphs, and line counts for optimal text readability.
Accurate estimates for silent reading duration (~200 wpm) and spoken presentation time (~130 wpm) for public speaking.
Security Features & Technical Specifications
PBKDF2 Key Stretching
Your master passphrase undergoes 100,000 hashing iterations using SHA-256 with a unique 16-byte random salt to derive a 256-bit AES encryption key, rendering online and offline brute-force attacks computationally impractical.
AES-256-GCM Cryptography
Galois/Counter Mode (GCM) delivers authenticated encryption. Any tampering or file corruption in disk storage is instantly detected and rejected during decryption attempts.
Zero Metadata Leakage
Note titles, category tags, and body contents are combined into a single structured string before encryption. Inspecting IndexedDB reveals zero plaintext titles or metadata.
Instant Panic Wipe
Triggering the panic button immediately clears in-memory decryption keys, unloads decrypted notes from JavaScript state, and locks the workspace instantly.
Encrypted .vault Backups
Export your full vault to a portable encrypted `.vault` file for offline storage or transfers across devices without exposing plaintext notes.
UI Unlock Throttling
Provides persistent attempt delays after consecutive wrong passwords to prevent rapid manual mis-entry. The primary defense against brute-force guessing remains the PBKDF2 derivation cost.
Threat Model Notice: Offline Storage & Shared Drives
When you export a .vault backup or store notes in IndexedDB, the data is strongly protected by AES-256-GCM. However, if an attacker obtains a copy of your .vault file (e.g., from an unencrypted USB drive or public cloud folder), they can attempt an offline brute-force attack using dedicated GPU hardware without incurring browser unlock rate limits.
To maximize security against offline cracking, always choose a multi-word passphrase (e.g., 4 or 5 random words). Our PBKDF2 key stretching makes offline dictionary attempts extremely expensive per candidate password.
How to Use the Encrypted Vault & Text Converter: Step-by-Step
Enter a 6 to 128 character master password or passphrase on initial launch. The password strength meter provides real-time complexity feedback. Optionally set a personal hint to prompt your memory later.
Draft notes or import `.md`/`.txt` files. Click the word count badge to open document insights and monitor words, characters, sentence count, reading time, and speech duration.
Click Export on any note to download rendered text into Word (.doc), Markdown (.md), Rich Text (.rtf), Plain Text (.txt), CSV spreadsheet, HTML, or Print to PDF.
Open Settings and select Export Encrypted .vault Backup for off-device cold storage. To restore on another device, click Restore .vault on the lock screen and input your master password.
Frequently Asked Questions (FAQ)
Q: Can I convert text to PDF, Word (.doc), and Markdown (.md)?
Yes. Click the Export button on any note to convert and download your text into 8 universal file formats including PDF, Word (.doc), Markdown (.md), Rich Text (.rtf), CSV spreadsheet, HTML, and JSON.
Q: How does the online word counter and speech time calculator work?
As you type, the document analytics engine parses your text in real time to calculate total words, characters (with and without spaces), sentence count, paragraph count, silent reading time (~200 wpm), and presentation speech duration (~130 wpm).
Q: Is my master password sent to any server?
No. This application runs entirely client-side. Key derivation and AES encryption happen exclusively inside your web browser engine via JavaScript and Web Crypto API.
Q: Are note titles and tags protected as well?
Yes. Metadata such as titles and tags are packaged with the note body into a JSON string before applying AES-256-GCM. Unencrypted metadata is never stored in disk storage.