The Privacy Problem
We noticed most note-taking apps forced users to choose between convenience and security. Either you got powerful features but sacrificed privacy, or got strong encryption with clunky interfaces. There had to be a better way.
Black Box Diary
Where your thoughts meet intelligence
Private
End-to-end encrypted diary that only you can access
Intelligent
AI that understands and organizes your thoughts
Fast
Capture ideas instantly, anywhere
Military-Grade Encryption
AES-256 encryption with zero-knowledge architecture
Free Tier
20 notes + 200 meeting minutes
Global Sync
Conflict-free sync across all your devices
Our Beginning
Building the Solution
Our small team of security engineers and AI researchers spent months prototyping a system that could offer intelligent features without ever accessing raw user data. The breakthrough came with our proprietary encrypted AI architecture.
Where We're Headed
Today we're focused on pushing the boundaries of what private AI can achieve. Every day brings new challenges as we work to make Black Box Diary the most capable yet trustworthy note-taking platform available.
Never store unencrypted data
Process all AI locally when possible
Ready to upgrade your thinking?
Start Your Private DiaryNo credit card required · 20 free notes + 200 free minutes