Review

Capacities: A serious PKM tool with a narrow idea of success

Capacities is strongest for individuals who want an object-based knowledge workspace with contextual AI, but it only makes sense if you actually want its model of how notes should work.

Last updated April 2026 · Pricing and features verified against official documentation

Most note-taking apps still ask you to think in folders. Capacities asks you to think in objects, which sounds fussy until you see what it does with people, books, projects, meetings, and ideas. The product is built around a simple wager: if your notes behave more like structured things than flat pages, they become easier to connect, query, and reuse later.

That wager gives Capacities a sharper identity than most PKM apps manage. The free core is genuinely usable, Pro adds contextual AI, smart queries, calendar integration, task actions, and reading imports, and the company keeps pushing the product toward a single-user knowledge system rather than a general-purpose workspace. The result is coherent in a way that many broader tools are not.

The case for Capacities is strong if you are a writer, researcher, student, or solo operator who wants a calm place to build a connected knowledge base without endless setup. It is also one of the better consumer privacy stories in this category: GDPR-compliant, EU-hosted, and explicit about what happens to AI inputs.

The case against it is just as clear. Capacities is opinionated, desktop-leaning, and built for individuals rather than collaboration-heavy teams, so people who want a simple notebook or a shared operating system will feel the structure before they feel the benefit. Capacities is excellent when you want a thinking tool and merely fine when you want a dumping ground.

What the Product Actually Is Now

Capacities is a personal knowledge workspace built around objects and object types rather than files and folders. Notes can represent people, books, projects, meetings, quotes, or custom types, and the app uses backlinks and unlinked mentions to surface relationships you would otherwise miss.

The current product is broader than note-taking alone. The free tier covers the core workspace, while Pro adds AI chats, auto-fill, smart queries, calendar integration, task actions, reading imports from Readwise and Kindle, a public API, and desktop and mobile apps. Capacities also offers a Believer tier for users who want to support the company and get early access, which tells you the product is still being shaped around a very specific idea of knowledge work.

Strengths

Objects give the app a real model. Capacities is compelling because its structure does useful work instead of feeling decorative. A person, a paper, a meeting, or a project can each have its own properties and views, which makes retrieval and reuse feel more natural than in a plain notes app. The tradeoff is real: you have to learn its grammar before the payoff shows up.

The free core is not a bait-and-switch. The company says the core product will remain free, and the app store listing backs that up with a usable free tier and no forced upgrade gate for basic capture and linking. That matters because many PKM tools are only pleasant after you pay; Capacities lets you test whether the object model fits your thinking before you spend anything.

Pro adds context instead of clutter. Capacities’ AI features are built around the notes you already have, not a generic blank chat box. The product can answer questions about a note, auto-fill object properties, summarize or rewrite content, and help organize queries and calendar context around the same workspace. That is a better use of AI than most note apps manage, and the company has also signaled a bring-your-own-key path for AI-heavy users.

Calendar and reading imports make it stickier. Bringing calendar events, tasks, Readwise, and Kindle highlights into the same system gives Capacities a credible claim to being a working environment rather than a digital scrapbook. That is useful for people who read, meet, and collect references all day, because the app can turn those inputs into connected objects instead of forcing them into separate tools.

Weaknesses

It asks you to buy into its worldview. The object model is the product’s biggest advantage and its biggest friction point. People who like loose capture or folders will feel the overhead quickly, and users who just want a place to jot down notes will not need the extra structure. Capacities rewards commitment, but it does not flatter casual use.

Teams are not the center of gravity. Capacities is designed around individuals first, and the company says so plainly in its principles. That keeps the product focused, but it also makes it a weaker fit for teams that need shared docs, permissions, admin controls, and a collaborative operating system. If that is the job, Notion AI is the more obvious starting point.

Mobile behaves like a companion, not the main stage. Capacities ships mobile apps, but the product still presents itself as a desktop-first environment for deep thinking and structured capture. That is fine if you mainly work from a laptop, and less fine if your workflow depends on phone-first editing or constant context switching. The app is broad in platform coverage and still narrow in how it expects you to work.

The paid tier is good value only if you actually use the extras. Pro is not expensive in absolute terms, but it is not a bargain if you only need a nicer notebook. The moment you stop using AI chats, smart queries, calendar links, and task actions, the subscription starts looking like a premium for a workflow you may not need. Casual note-takers should stay on free.

Pricing

Capacities’ pricing makes the target user obvious. Free is the real starting point and the company says it will stay free forever. Pro is the only tier most individuals will actually need, and the current App Store listing shows it at $17.99 per month or $199 per year. There is also a 14-day free trial with no credit card required.

That structure is sensible for a personal knowledge tool. Most users either want the free core and nothing else, or they want Pro because they plan to use the object model, AI chats, queries, and calendar integration every day. There is no team ladder to climb here, which is a clue about the business as much as the product: Capacities is selling personal depth, not organizational breadth.

Believer is best read as a patronage tier. It exists for users who want to support the company and get early access to upcoming work, not because it unlocks a separate workflow that most buyers will depend on. The pricing trap is simple: if you are not using the contextual features, stay free. If you are, Pro is the value tier.

Privacy

Capacities has a better privacy story than most consumer AI notes apps. The company says it is GDPR-compliant, stores data on encrypted servers in the EU, and lets you revoke consent or disable AI functions in the app settings.

The AI policy is unusually explicit. When AI is enabled, Capacities processes notes, selected text, media, chat inputs, and metadata, then transmits only the context needed to third-party AI providers. The company says those providers do not use the content to train models and only retain it temporarily for processing. Chat histories are stored by default in your notes, so the product is clear about where that output lives.

That is a strong consumer privacy posture, but it is still a cloud service. Content may be transmitted outside the EU or EEA under standard contractual clauses, and the moment you turn on AI you are trusting third-party model providers with selected note content. For ordinary personal knowledge work, that is a reasonable trade. For highly sensitive regulated work, it is a reminder to read the policy closely.

Who It’s Best For

• The solo researcher, writer, or student who wants notes, readings, and ideas to connect automatically instead of living in separate folders.
• The knowledge worker who uses calendar events, tasks, and reading highlights as raw material for ongoing projects.
• The person who likes structured thinking and is willing to learn a more opinionated system in exchange for better retrieval later.
• The privacy-conscious user who wants an EU-based, GDPR-aligned consumer product with a clear AI data policy.

Who Should Look Elsewhere

• Teams that need shared docs, collaboration controls, and a broader workspace should start with Notion AI.
• Users who mostly want source-grounded Q&A over a bounded document set should compare NotebookLM.
• People who want capture-first recall with less structure should evaluate Mem instead.
• Casual note-takers who mainly need a clean place to store text should probably stay with a simpler app and skip the object model entirely.

Bottom Line

Capacities is one of the few note tools that knows exactly what it believes. It wants your notes to behave like structured knowledge, and it gives you enough AI, linking, and context to make that idea useful rather than merely clever.

That makes it a strong buy for individuals who actually want a personal knowledge system and a poor fit for anyone who just wants a tidy notebook. If the object model fits the way you think, Capacities has real staying power. If it does not, the product will feel like work before it feels like help.