Free: 2,500 words per month, all intensities, API access (60 requests/min), document history, no credit card required. Pro: $19/month for 100,000 words per month, 300 requests/min API limit, priority support. Word pack: $9 for 50,000 words with no expiration or subscription.
Free: 10 credits (one-time). Monthly: $7/mo for 70 credits. Yearly: $65/yr for 600 credits.
Key features
Self-hosted fine-tuned language model
Three intensity levels per request
3-5 second average response time
Content never used for training
Works with any AI model
Webhook support for real-time events
Dashboard with API key management
Document history and web-based interface
TYPE-FORMULA pipeline that extracts insight types (diagnostic, wisdom, contrarian, data-backed, framework, story) and applies viral structures
Knowledge Bank to store, browse, and reuse extracted insights
10+ viral formula structures including parallel repetition, conditional framework, and bridge analogy
Chrome extension for scheduling posts directly to Substack
Rich-text editor with HTML and plain text export
MCP integration for Claude and Cursor
Automatic article URL processing from published or draft posts
Priority processing for paid plan users
What makes it different
Rewrites sentence structure and rhythm, not just synonyms
Completely private with no data sharing or third-party APIs
Simple integration with any HTTP client
Generous free plan without credit card requirement
API-first design for programmatic use at scale
Designed specifically for Substack writers with formulas trained on viral patterns
Two-stage TYPE-FORMULA process instead of generic AI summarization
Knowledge Bank compounds over time as more articles are processed
From URL to scheduled post in minutes with no copy-paste needed
ToHuman
Quick Viral Notes