Free
Free
Starter tier allows five captures and five AI chats per day with up to 5MB per file.
- Access
- Starter tier allows five captures and five AI chats per day with up to 5MB per file.
SigmaNote - your second brain
● Identity checkedResearch · Vendor site 2026-10-04
SigmaNote is a cross-platform second-brain app for capturing PDFs, EPUBs, office documents, web pages, YouTube transcripts, and voice notes, then chatting with AI grounded in your library. It syncs across iOS, macOS, and web with encryption-focused privacy claims.
- Category
- Research
- Free access
- Starter tier allows five captures and five AI chats per day with up to 5MB per file.
- API access
- Not confirmed
Is SigmaNote - your second brain right for you?
A good fit for
Students, researchers, and professionals who consolidate documents and ask AI questions over their own materials.
Before you choose
Premium tiers are referenced but no explicit monthly USD prices appear in public structured data.
Own your knowledge
SigmaNote unifies imports and AI chat so personal research libraries stay searchable and actionable across devices.
What it can do
Features & capabilities
Unknown is different from unavailable. Each fact carries its own evidence.
| Capability | Value | Evidence | Checked |
|---|---|---|---|
| Multi-format import | Schema lists PDF, EPUB, Word, PowerPoint, Excel, web, and YouTube transcript capture. | Facts sourced | 2026-10-04 |
| Grounded AI chat | Marketing describes AI agents that answer using your stored knowledge base. | Facts sourced | 2026-10-04 |
| Encryption claims | FAQ states notes use end-to-end encryption with TLS 1.3 sync and no training on user content. | Facts sourced | 2026-10-04 |
Understand the total cost
SigmaNote - your second brain pricing & plans
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Explore toolThe practical questions
Frequently asked questions
Is SigmaNote free to use?
FAQ describes a free Starter tier with five daily captures and chats plus 5MB per file limits.
What file formats does SigmaNote support?
FAQ lists PDF, EPUB, Office formats, web articles, YouTube links, and iOS share sheet sources.
What is SigmaNote - your second brain used for?
SigmaNote is a cross-platform second-brain app for capturing PDFs, EPUBs, office documents, web pages, YouTube transcripts, and voice notes, then chatting with AI grounded in your library. It syncs across iOS, macOS, and web with encryption-focused privacy claims.
Does SigmaNote - your second brain have a free plan?
Starter tier allows five captures and five AI chats per day with up to 5MB per file.. This record lists ongoing free access; check the plan limits before starting.
How much does SigmaNote - your second brain cost?
No paid monthly price is listed; this record treats the product as free to start. See the plan cards for entitlements, billing commitments and seat minimums.
Can I use SigmaNote - your second brain through an API?
Not confirmed. API access and subscription access may have different terms; consult the linked sources.
What should I check before choosing it?
Premium tiers are referenced but no explicit monthly USD prices appear in public structured data.
Price history
No retained pricing changes yet. A current price alone does not establish a historical trend.
How this profile is supported
Identity and profile
Reviewed vendor source
Read original source ↗Facts apply to the named version and check date. Send a sourced correction if something changed.