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Nebula: Secure Knowledge Engine

Your notes, your rules. Post-quantum encrypted, beautifully organized, and free to sync across every device.

Note-Taking Without Compromise

Nebula is a markdown-first knowledge engine built for people who take their notes — and their privacy — seriously. Write in plain markdown, visualize connections with a knowledge graph, and protect everything with encryption that will outlast quantum computers.

  • Local-first — your notes never leave your devices
  • Post-quantum encryption — ML-KEM-1024 + AES-256-GCM
  • Free sync — P2P across all your devices, no cloud
  • Cross-platform — Windows, macOS, Linux (mobile coming soon)
Nebula editor showing a markdown note with wiki-links, knowledge graph, and vault sidebar

Built for Serious Note-Takers

Every feature designed to help you think clearly and protect what matters.

Markdown-First Editing

Write in pure markdown with wiki-links, backlinks, tags, and a split editor. Your notes stay portable — no proprietary formats, ever.

Knowledge Graph

Visualize connections between your notes with an interactive graph view. Discover patterns and relationships across your entire knowledge base.

Encrypted Vault System

Two vault tiers only: Standard (no encryption at rest) and Secure with AES-256-GCM encryption at rest. Choose the level that fits each situation.

Post-Quantum Encryption

Secure vaults use ML-KEM-1024 key encapsulation with AES-256-GCM — quantum-resistant cryptography protecting your data today and tomorrow.

Free Device Sync

Peer-to-peer sync via encrypted relay — no cloud storage, no subscriptions. Your notes stay on your devices, always in sync.

Command Palette

Navigate your entire workspace from the keyboard. Fast file switching, vault actions, and search — all without touching the mouse.

Two Vaults. Your Choice.

From everyday notes to encrypted privacy — choose the security level that fits.

Standard Vault

Free

Plain markdown files on disk with no encryption at rest. Fast and portable for everyday notes you access frequently.

Secure Vault

Free

Password-protected with AES-256-GCM encryption. Notes are encrypted at rest and decrypted only in memory. Ideal for sensitive information.

Nebula vault diagram showing Standard and Secure vault tiers

Your Notes. Every Device.

Native desktop apps with free sync. Mobile coming soon.

Windows

x64 installer

macOS

Intel / Apple Silicon

Linux

x64 / ARM64

iOS and Android apps are in active development.

Get Nebula

Free forever. Upgrade to unlock more.

Perpetual Annual Save 60%

Nebula Free

$0 forever
  • Markdown editor with wiki-links & backlinks
  • Standard (not encrypted at rest) and Secure encrypted vaults
  • Basic search across all notes
  • Interactive knowledge graph view
  • Free device sync (up to 3 devices)
  • Cross-platform (Windows, macOS, Linux)
  • Community support

Secure checkout via Stripe

Recommended

Nebula Pro

$20 one-time
  • Everything in Free
  • Semantic / AI-powered search
  • Sync up to 5 devices
  • Priority support

Secure checkout via Stripe

Nebula Forensics

$99 one-time
  • Everything in Free
  • Entity recognition in notes
  • Typed relationships between entities
  • Timeline view across notes
  • Screenshot annotation tools
  • Entity search & filtering
  • Priority support

Secure checkout via Stripe

Need volume licensing or have questions? Contact us.

Frequently Asked Questions

Is Nebula really free?
Yes. The Free tier is fully functional with no limits on notes, vaults, or sync. Pro and Forensics add specialized features for power users and investigators.
How does device sync work?
Nebula syncs peer-to-peer via an encrypted relay server. Your notes are never stored on any cloud — they pass through the relay end-to-end encrypted and land directly on your other devices.
What is the Secure Vault?
The Secure Vault encrypts your notes at rest using AES-256-GCM with key derivation via ML-KEM-1024 — quantum-resistant cryptography. Notes are decrypted only in memory while you work with them. Standard Vault notes are not encrypted at rest.
Do I need Pro AND Forensics?
No — they are separate tiers for different use cases. Pro is for power users who want AI-powered semantic search and additional device slots. Forensics is for investigators who need entity recognition, timeline analysis, and typed relationships.
What platforms are supported?
Nebula runs natively on Windows, macOS (Intel and Apple Silicon), and Linux. Mobile apps for iOS and Android are in development.
How are updates delivered?
Updates are delivered in-app. Perpetual license holders receive all updates indefinitely. Annual subscribers receive updates for the duration of their subscription, which renews automatically.

Ready to Secure Your Knowledge?

Join thousands of note-takers who choose privacy without sacrificing power.

Download Nebula Free View Pricing

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