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Installation

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NuGet package

dotnet add package PDF4LLM
Or via the Visual Studio Package Manager Console: 
Install-Package PDF4LLM
Or by adding the package reference directly to your .csproj: 
<PackageReference Include="PDF4LLM" Version="*" />

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Dependencies

PDF4LLM depends on MuPDF.NET and lists it as a NuGet dependency. It is installed automatically — you do not need to add MuPDF.NET separately. After installation, two native DLLs are required at runtime:
FileContents
mupdfcpp64.dllThe MuPDF C library with C++ bindings
mupdfcsharp.dllThe C# bindings for MuPDF
The NuGet package copies these to your project’s output directory on build. If your deployment environment does not allow automatic DLL placement, both files must be present in the same directory as your application executable, or on a path accessible via the PATH environment variable.

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Supported targets

Target frameworkSupported
.NET 8.0✓
.NET 7.0✓
.NET 6.0✓
.NET 5.0✓
.NET Standard 2.0✓
.NET Framework 4.8✓
.NET Framework 4.7.2✓
.NET Framework 4.6.1✓
PDF4LLM targets .NET Standard 2.0, making it compatible with any framework that implements that standard.

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Verify the installation

Add a using directive and call ToMarkdown on any PDF to confirm everything is wired up: 
using MuPDF.NET;
using PDF4LLM;

string markdown = PdfExtractor.ToMarkdown("document.pdf");
Console.WriteLine(markdown);

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Resolving the assembly conflict

If you see this error at build or runtime: 
An assembly with the same simple name 'PDF4LLM' has already been imported
Your installed version of MuPDF.NET already bundles PDF4LLM internally. Having both packages referenced simultaneously causes the conflict. Fix: Remove the explicit PDF4LLM package reference and rely on the bundled version: 
dotnet remove package PDF4LLM
Or remove the line from your .csproj manually: 
<!-- Remove this line -->
<PackageReference Include="PDF4LLM" Version="*" />
The API is identical either way — using PDF4LLM; and PdfExtractor.* work regardless of which package supplies the assembly.
A future release of MuPDF.NET will stop bundling PDF4LLM, allowing both packages to coexist without conflict. Until then, use one or the other.

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Optional: OCR support

OCR is not required for most PDFs. Enable it only when working with scanned documents or pages that contain no selectable text. OCR requires Tesseract to be installed on the host system and available on the PATH. PDF4LLM does not bundle Tesseract. Windows — Download the installer from UB Mannheim Tesseract builds and add the install directory to your PATH. macOS 
brew install tesseract
Linux (Debian / Ubuntu) 
sudo apt-get install tesseract-ocr
Verify Tesseract is reachable: 
tesseract --version
See the OCR guide for language pack installation and usage.