# Layout Blocks

> A scrollable review panel that lists OCR/layout-detection blocks (headings, paragraphs, tables, figures, etc.) from a document with type badges, confidence scores, and page numbers, for inspecting the text layer behind scanned or image-heavy PDFs.

- Author: [Extend](https://21st.dev/@extend)
- Library: Extend
- License: MIT
- Tags: PDF
- npm dependencies: rehype-raw, remark-gfm, @base-ui/react, react-markdown, rehype-sanitize, @tanstack/react-virtual
- Live preview: https://21st.dev/@extend/components/layout-blocks

## Install

```bash
npx shadcn@latest add "https://21st.dev/r/extend/layout-blocks?api_key=$API_KEY_21ST"
```

Requires a 21st API key (generate one at https://21st.dev/mcp) passed as `API_KEY_21ST`. Free accounts get a limited number of installs per day; unlimited on a paid plan — see https://21st.dev/pricing.

Full component directory: https://21st.dev/llms.txt · More like this: https://21st.dev/community/components/s/pdf.md