TheBrain review

TheBrain is a visual knowledge platform built around connected items called thoughts. You can link notes, files, web pages, people, projects, research, and plans, then navigate their relationships in a network rather than relying only on folders or a linear list. Card View, Mind Map, and Tree View offer different ways to explore that network.

Search is meant to bring up related thoughts and their connected notes, files, and links. The built-in Cerebro AI can summarize, search, suggest links, and create content using information in your Brain. TheBrain also supports shared knowledge networks for teams, with multi-user editing on its team plan.

The pitch is not simply “make a mind map.” It is to use a visual map as the front end for a broader store of working knowledge. That approach will suit people who think in connections; it may be less natural if you mainly want a conventional notes app.

The main advantage is that relationships are part of the interface, not just metadata behind a search box. A Reddit user who has used TheBrain for years describes it as a visual way to keep work, genealogy, and personal research in separate Brains. Another commenter explains that the current thought moves to the center while related items remain visible, which can help keep a large knowledge base navigable.

It also accepts a broad mix of material: the product description lists notes, files, links, web pages, research, meetings, ideas, and plans. Cerebro AI adds ways to summarize and work with that stored knowledge, though the free plan only includes a small daily allowance.

The free tier is unusually usable for trying the core model: according to the pricing details, it allows unlimited thoughts, links, and Brains, plus public Brains with free sync and sharing. It is available for personal and commercial use. If the visual approach fits, paid plans add private sync, more storage, and—on TeamBrain—multi-user editing and shared Brains.

The free plan’s private sync is capped at 1,000 thoughts, and synced attachments are limited to 100 MB. The Pro Service plan raises those limits to unlimited private sync and 30 GB of online storage, but costs $16 per user per month or $15 per month when billed annually. TeamBrain is $29 monthly or $25 per month billed annually. Annual terms are billed yearly, so the lower figure is not a month-to-month price.

Storage and AI allowances still have ceilings: TeamBrain includes 100 GB, while Max Service includes 250 GB and four times the Cerebro AI usage of TeamBrain, resetting daily. The pricing details say storage overages require a tier upgrade; paid add-ons and overage prices are not published. Enterprise pricing and seat limits are also not published.

Export deserves scrutiny before you move a large archive in. One Reddit user reports limited export options and difficulty carrying relationships into another format. That is an individual report, not a published product limit, but it flags a practical switching risk: check whether you can get your data back in the structure you need.

The published pricing details, checked November 6, 2026, list a free plan and paid plans from $15 per user per month when billed annually. Pro Service is $16 monthly or $15 per month on an annual term. It includes unlimited private sync and 30 GB of storage; free private sync is capped at 1,000 thoughts and 100 MB of synced attachments.

TeamBrain costs $29 monthly or $25 per month annually. That is a $10-per-user monthly jump from annual Pro, for multi-user editing, unlimited shared Brains and 100 GB of storage. Max Service rises to $48 monthly or $40 annually, adding four times the Cerebro AI usage and 250 GB. Enterprise pricing is custom.

Annual rates are billed yearly, not month to month. The pricing details say paid add-ons and overage prices are not published; exceeding cloud storage requires a tier upgrade. Free includes limited daily AI, while Pro's full allowance resets daily.

TheBrain is built around connected notes, files, links and projects, so moving an existing knowledge system may involve more than transferring documents: you may also need to recreate relationships and structure. The published material does not publish migration steps or supported import formats, so check those before committing a large archive.

Our verdict flags easy data export as a weakness, but it does not specify export formats or limits. We would verify what can be exported, and whether connections between items survive, before making TheBrain the only home for important research. The plan details also make private sync a paid consideration beyond the free plan’s 1,000-thought limit.

No Reddit posts or comments were included in the published material, so we can’t substantiate a claim about why users leave. For now, the evidence supports treating export and migration details as questions to resolve—not assuming a painless move in either direction.