> ## Documentation Index
> Fetch the complete documentation index at: https://docs.pdf4llm.com/llms.txt
> Use this file to discover all available pages before exploring further.

# API

> Complete reference for all PDF4LLM methods and types.

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## Extraction methods

The three primary extraction methods share a common interface — they all accept a file path string or an open `MuPDF.NET.Document`, support the `pages` parameter for partial extraction, and return a string you can write directly to disk or pass downstream.

<CardGroup cols={1}>
  <Card title="ToMarkdown()" icon="markdown" href="/dotnet/api/PdfExtractor#tomarkdown">
    Extract content as a GitHub-compatible Markdown string. The primary method for LLM ingestion and RAG pipelines. Supports image extraction, OCR, and per-page output via `LlamaMarkdownReader`.
  </Card>

  <Card title="ToJson()" icon="brackets-curly" href="/dotnet/api/PdfExtractor#tojson">
    Extract content as structured JSON with bounding boxes and layout data for every block on the page. Use for custom pipelines, positional filtering, and debugging extraction output.
  </Card>

  <Card title="ToText()" icon="align-left" href="/dotnet/api/PdfExtractor#totext">
    Extract content as plain text, stripped of all Markdown syntax. Use for search indexing, NLP pipelines, and systems that render Markdown literally.
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## Layout and structure methods

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  <Card title="ParseDocument()" icon="table-columns" href="/dotnet/api/PdfExtractor#parsedocument">
    Analyse the visual layout of a document and return a typed `ParsedDocument` object — pages, text blocks, tables, and image regions — with bounding boxes and reading order. The in-process equivalent of `ToJson()`.
  </Card>

  <Card title="GetKeyValues()" icon="text-size" href="/dotnet/api/PdfExtractor#getkeyvalues">
    Extract all interactive AcroForm field names, values, and page locations from a PDF. Use for structured data extraction from filled-in forms.
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## Reader types

<CardGroup cols={1}>
  <Card title="PDFMarkdownReader" icon="database" href="/dotnet/api/PdfExtractor#llamamarkdownreader">
    A LlamaIndex-compatible document reader. Created via `PdfExtractor.LlamaMarkdownReader()`. Loads a PDF and returns one `LlamaDocument` per page, each with Markdown text and metadata including page number and source file path.
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## Return types

<CardGroup cols={1}>
  <Card title="ParsedDocument" icon="rectangle" href="/dotnet/api/PdfExtractor#parsedocument">
    Typed .NET object returned by `ParseDocument()`. Contains a list of `ParsedPage` objects, each with its blocks, tables, images, and dimensions.
  </Card>

  <Card title="FormField" icon="list" href="/dotnet/api/PdfExtractor#getkeyvalues">
    Represents a single AcroForm field returned by `GetKeyValues()`. Exposes `Name`, `Value`, and `Page` properties.
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## Quick reference

| Method / Type                        | Returns               | Key parameters                                                              |
| ------------------------------------ | --------------------- | --------------------------------------------------------------------------- |
| `PdfExtractor.ToMarkdown()`          | `string`              | `pages`, `writeImages`, `embedImages`, `useOcr`, `ocrLanguage`, `forceText` |
| `PdfExtractor.ToJson()`              | `string` (JSON)       | `pages`, `showProgress`                                                     |
| `PdfExtractor.ToText()`              | `string`              | `pages`, `useOcr`, `ocrLanguage`, `forceText`                               |
| `PdfExtractor.ParseDocument()`       | `ParsedDocument`      | `pages`, `useOcr`, `ocrLanguage`                                            |
| `PdfExtractor.GetKeyValues()`        | `List<FormField>`     | `doc` only — no `pages` parameter                                           |
| `PdfExtractor.LlamaMarkdownReader()` | `PDFMarkdownReader`   | —                                                                           |
| `PDFMarkdownReader.LoadData()`       | `List<LlamaDocument>` | `filePath`, `extraInfo`                                                     |