Sidenote vs PDF.ai
PDF.ai is an upload-first PDF chat app with a developer API; Sidenote reads whatever you already have open, PDF or not, and cites every answer back to the exact passage.
Reads the document you already have open and grounds every claim in a checked citation.
Upload a PDF, chat with it, and wire the same chat into your own app via API.
Should you use Sidenote or PDF.ai?
Choose Sidenote if…
Choose Sidenote if you read across PDFs, web articles, Google Docs, Notion, Confluence and SharePoint, and you want every answer grounded in a citation that scrolls and highlights the exact passage on the live page, with any quote it cannot verify dropped before you see it.
Choose PDF.ai if…
Choose PDF.ai if you work almost entirely in PDF files and want a developer API or an embeddable chat widget to put PDF chat inside your own product, or need SOC 2 Type II credentials for procurement.
Both let you upload a PDF, chat with it, summarize it, run OCR on scans, cite answers back to the document, and start on a free tier. The real split is scope: PDF.ai is a PDF workspace and API you send files to, while Sidenote reads whatever you already have open, web pages included, and validates every citation against the source before showing it.
Sidenote vs PDF.ai: feature by feature.
| Capability | Sidenote | PDF.ai |
|---|---|---|
| Upload your own PDFs | Yes | Yes |
| Chat with a document | Yes | Yes |
| Reads scanned PDFs with built-in OCR | Yes | Yes |
| No-login free tier | Yes | Yes |
| Ask across many documents at once | Yes | Yes |
| Reads the page or document you already have open | Yes | No |
| Works on web articles & live web pages | Yes | No |
| Works on private Confluence, Notion & SharePoint pages | Yes | No |
| Citations scroll & highlight the exact passage on the live page | Yes | Partial |
| Server-side citation check drops unsupported claims | Yes | No |
| Developer API to build PDF chat into your own app | No | Yes |
| SOC 2 Type II certification | No | Yes |
Last reviewed: 3 July 2026.
Verified against pdf.ai and third-party listings of its pricing and features in July 2026. PDF.ai centers on uploaded PDF files and offers a developer API, an embeddable chat widget and SOC 2 Type II certification that Sidenote does not; its answers link back to sections of the uploaded PDF. Sidenote reads many source types in place, web pages included, and additionally validates each cited quote against the document, dropping any it cannot find. Check both sites for the latest details. The cross-document row is powered by Sidenote Collections.
A PDF workspace you send files to, or a reader already on the page.
PDF.ai is built around the PDF file: you upload a document to its web app, then ask questions, request summaries and extract data, with answers linked back to the relevant sections of the file. Its standout for builders is the developer API and embeddable chat widget, letting teams drop PDF chat straight into their own products, backed by SOC 2 Type II certification.
Sidenote works the other way around. It lives in your browser side panel and reads whatever is in front of you (a PDF, a web article, a Google Doc, a Notion or Confluence page) with no upload step, and every answer is cited to the exact passage, with clicks that scroll the live page to the source. A server-side check then validates each quote against the document and drops anything it cannot ground.
You are checking a claim buried on page 40 of a scanned contract. In PDF.ai you upload the file, ask your question, and click a source link to jump to the referenced section inside its PDF viewer. In Sidenote you open the same PDF in your browser, ask your question, and click the citation to jump straight to the highlighted clause on the live page. The server has already dropped any quote it could not find in the document.
Where PDF.ai is the better tool.
PDF.ai does several things genuinely well, and if your world is PDFs and product integrations it is a strong choice.
A real developer API
PDF.ai exposes a web API and an embeddable chat widget, so teams can build PDF parsing, extraction and chat directly into their own apps. Sidenote has no public API.
PDF-first workflow
For heavy PDF work (uploading, OCR, extraction and chat in one focused workspace) PDF.ai keeps everything centered on the file, and offers a Chrome extension for chatting with PDFs as you browse.
Enterprise-friendly credentials
PDF.ai advertises SOC 2 Type II certification and paid team and Enterprise plans, which can matter for procurement and larger rollouts.
Sidenote vs PDF.ai: common questions
Read anything. With citations.
Sidenote reads the page you already have open and cites every claim to the source. The 7-day Pro trial is opt-in, no card required.
7-day Pro trial · No card required · Free plan forever