AI Tool Comparison
Capacities vs Superhuman
A side-by-side breakdown to help you pick the right tool for your workflow.
Capacities
Organize notes as typed objects, people, books, projects, that link automatically, building a connected knowledge base without manual folders or tags.
Superhuman
Fly through your inbox with an AI-accelerated email client. Grammarly acquired Superhuman in October 2025 and expanded it into a broader Suite with AI docs and agent tools.
Bottom Line
Last reviewed: August 2026
Capacities and Superhuman both sit in Productivity, but they're built around different use cases within it. Capacities runs on a freemium model while Superhuman runs on a paid-only plan, which alone may settle it if budget or a free tier is a hard requirement. Superhuman carries the higher rating (4.7 vs 4.5), but a gap that size rarely overrides a real workflow fit on its own.
Choose Capacities if…
Best for anyone who wants their notes organized as typed objects with real connections, not just pages in folders, and its edge is aI surfaces related notes automatically, reducing the 'I know I captured this somewhere' problem. A genuinely different and thoughtful note-taking model, it demands more upfront structure thinking than just dumping notes. Lean toward Superhuman instead if every action is keyboard-driven, with AI-drafted replies that hold up against manual writing matters more for your use case.
Choose Superhuman if…
Best for professionals processing high email volume who want the fastest possible path to inbox zero, and its edge is every action is keyboard-driven, with AI-drafted replies that hold up against manual writing. Genuinely the fastest email client available, the price and invitation-only access make it overkill for casual use. Lean toward Capacities instead if aI surfaces related notes automatically, reducing the 'I know I captured this somewhere' problem matters more for your use case.
| Attribute | Capacities | Superhuman |
|---|---|---|
| Category | Productivity | Productivity |
| Pricing | freemium | paid |
| Pricing Detail | Free (5GB) / ~$10-12/mo Pro (annual) | $30/mo Starter / $40/mo Business |
| Rating |
Key Features
Capacities
- Object-based structure
- Auto bi-directional links
- AI knowledge queries
- Daily notes
- Web clipper
- Cross-device sync
Superhuman
- AI reply drafts
- Email summarization
- Keyboard-first design
- Split inbox
- Auto follow-up reminders
Pros
Capacities
- •Object model creates natural connections that folder-based tools miss
- •AI surfacing of related notes reduces 'I know I captured this' friction significantly
- •Daily note format with backlinks integrates well with structured note-taking workflows
Superhuman
- •Genuinely fastest way to do email
- •AI drafts are excellent
- •Keyboard shortcuts for everything
- •Loved by power users
Cons
Capacities
- Object model requires upfront thinking about structure vs. just dumping notes
- Smaller ecosystem than Obsidian or Notion
Superhuman
- Expensive
- Requires invitation (exclusive)
- Gmail/Outlook only
- Overkill for casual email users