--- title: "Nutrient.SDK package for C# | Nutrient .NET SDK" canonical_url: "https://www.nutrient.io/guides/dotnet/csharp/" md_url: "https://www.nutrient.io/guides/dotnet/csharp.md" last_updated: "2026-10-08T00:00:00.000Z" description: "Overview of the Nutrient.SDK package — the modern, document-centric C# API in Nutrient .NET SDK — and how it relates to the GdPicture.API package." --- # Nutrient.SDK package The Nutrient.NET SDK ships in two NuGet packages. Both process PDF, Office, and image documents, and **one license key works with either** — pick the one that fits your project. `Nutrient.SDK` is the newer of the two: an idiomatic, document-centric C# API for current.NET. The guides in this section cover `Nutrient.SDK` only; the rest of the.NET SDK guides cover the `GdPicture.API` package. ## Choose your Nutrient.NET package | Criteria | **`Nutrient.SDK`** (new) | **`GdPicture.API`** (established) | | ----------------------------------- | -------------------------------------------------- | ------------------------------------------------------------------ | | Best for | New projects on current.NET | Existing apps, or broad framework support | | Target frameworks |.NET 10 |.NET 8.0 and.NET Framework 4.6.2 | | API style | Idiomatic, document-centric (`Document.Open(...)`) | Full GdPicture.NET toolkit (`GdPictureImaging`, `GdPicturePDF`, …) | | Install | `dotnet add package Nutrient.SDK` | `dotnet add package GdPicture.API` | | Namespace | `using Nutrient;` | `using GdPicture14;` | | Windows viewers (WPF/WinForms/MAUI) | — | Available as companion packages | - **Starting fresh on.NET 10?** Use `Nutrient.SDK` — follow the [getting started guide](https://www.nutrient.io/sdk/dotnet/getting-started/csharp.md). - **Maintaining an existing GdPicture.NET app, or need.NET Framework or the WPF/WinForms/MAUI viewers?** Stay on `GdPicture.API` — follow the [GdPicture.API getting started guide](https://www.nutrient.io/sdk/dotnet/getting-started.md). A Nutrient.NET SDK license key is valid for both packages, so either can be evaluated without a separate key. ## What the Nutrient.SDK package can do - Convert PDF, Office, and image documents - Edit PDFs, annotations, and form fields - Extract text and structured data - Run OCR on scanned documents - Export documents as PDF, images, HTML, or Markdown - Apply digital signatures ## Guides by topic - [Editor](https://www.nutrient.io/guides/dotnet/csharp/editor.md) — annotations, form fields, signatures, pages, and metadata - [Extraction](https://www.nutrient.io/guides/dotnet/csharp/extraction.md) — OCR, text, structured data, barcodes, and AI-powered extraction - [Conversion](https://www.nutrient.io/guides/dotnet/csharp/conversion.md) — PDF, Word, Excel, PowerPoint, HTML, Markdown, email, and CAD - [Templates](https://www.nutrient.io/guides/dotnet/csharp/templates.md) — Word template generation and PDF/UA template output - [Troubleshooting](https://www.nutrient.io/guides/dotnet/csharp/troubleshooting.md) — error handling - [Deployment](https://www.nutrient.io/guides/dotnet/csharp/deployment.md) — headless environments ## Resources - [Get started with Nutrient.SDK](https://www.nutrient.io/sdk/dotnet/getting-started/csharp.md) - [Nutrient.SDK API reference](https://www.nutrient.io/api/csharp.md) - [License activation](https://www.nutrient.io/guides/dotnet/csharp/license-activation.md) - [Sample downloads](https://www.nutrient.io/guides/dotnet/csharp/downloads.md) - [Nutrient.SDK changelog](https://www.nutrient.io/guides/dotnet/csharp/changelog.md) - [Nutrient.SDK on NuGet](https://www.nuget.org/packages/Nutrient.SDK) --- ## Related pages - [Changelog for Nutrient.SDK](/guides/dotnet/csharp/changelog.md) - [.NET SDK sample downloads](/guides/dotnet/csharp/downloads.md) - [License activation](/guides/dotnet/csharp/license-activation.md) ## Pages in this section - [Nutrient .NET SDK conversion guides](/guides/dotnet/csharp/conversion.md) - [Converting CAD files to PDF](/guides/dotnet/csharp/conversion/cad-to-pdf.md) - [Converting email files to PDF](/guides/dotnet/csharp/conversion/email-to-pdf.md) - [Converting a document from XLSX to PDF format](/guides/dotnet/csharp/conversion/excel-document-to-pdf.md) - [Converting HTML to PDF](/guides/dotnet/csharp/conversion/html-to-pdf.md) - [Converting a document from Markdown to PDF format](/guides/dotnet/csharp/conversion/markdown-to-pdf.md) - [Converting PDF pages to images](/guides/dotnet/csharp/conversion/pdf-pages-to-images.md) - [Converting PDF documents to Excel format for data analysis](/guides/dotnet/csharp/conversion/pdf-to-excel-document.md) - [Converting PDF documents to HTML format for web publishing](/guides/dotnet/csharp/conversion/pdf-to-html.md) - [Converting PDF documents to image format](/guides/dotnet/csharp/conversion/pdf-to-image.md) - [Converting PDF documents to Markdown format](/guides/dotnet/csharp/conversion/pdf-to-markdown.md) - [Converting PDF documents to PDF/A format](/guides/dotnet/csharp/conversion/pdf-to-pdf-a.md) - [Converting PDF documents to PDF/UA format](/guides/dotnet/csharp/conversion/pdf-to-pdf-ua.md) - [Converting PDF documents to PowerPoint presentations](/guides/dotnet/csharp/conversion/pdf-to-powerpoint-document.md) - [Converting a document from PDF to DOCX format](/guides/dotnet/csharp/conversion/pdf-to-word-document.md) - [Converting a document from PPTX to PDF format](/guides/dotnet/csharp/conversion/powerpoint-document-to-pdf.md) - [Preparing and troubleshooting PDF/A conversion](/guides/dotnet/csharp/conversion/prepare-and-troubleshoot-pdf-a-conversion.md) - [Converting a Word document to PDF while preserving comments](/guides/dotnet/csharp/conversion/word-document-to-pdf-including-comments.md) - [Converting a document from DOCX to PDF/UA format](/guides/dotnet/csharp/conversion/word-document-to-pdf-ua.md) - [Converting a document from DOCX to PDF format](/guides/dotnet/csharp/conversion/word-document-to-pdf.md) - [Nutrient .NET SDK deployment guides](/guides/dotnet/csharp/deployment.md) - [Chrome headless modes with C# SDK](/guides/dotnet/csharp/deployment/headless-modes-google-chrome.md) - [Nutrient .NET SDK editor guides](/guides/dotnet/csharp/editor.md) - [Adding annotations to a PDF document](/guides/dotnet/csharp/editor/add-annotations-to-pdf.md) - [Adding a custom page to a PDF document](/guides/dotnet/csharp/editor/add-custom-page-to-pdf.md) - [Adding interactive form fields to a PDF document](/guides/dotnet/csharp/editor/add-form-fields-to-pdf.md) - [Adding free text annotations to a PDF document](/guides/dotnet/csharp/editor/add-freetext-annotations-to-pdf.md) - [Adding invisible digital signatures to a PDF document](/guides/dotnet/csharp/editor/add-invisible-signature-to-pdf.md) - [Adding link annotations to a PDF document](/guides/dotnet/csharp/editor/add-link-annotations-to-pdf.md) - [Adding redaction annotations to a PDF document](/guides/dotnet/csharp/editor/add-redaction-annotations-to-pdf.md) - [Adding shape annotations to a PDF document](/guides/dotnet/csharp/editor/add-shape-annotations-to-pdf.md) - [Adding stamp annotations to a PDF document](/guides/dotnet/csharp/editor/add-stamp-annotations-to-pdf.md) - [Adding sticky note annotations to a PDF document](/guides/dotnet/csharp/editor/add-sticky-note-annotations-to-pdf.md) - [Adding text markup annotations to a PDF document](/guides/dotnet/csharp/editor/add-text-markup-annotations-to-pdf.md) - [Adding visible digital signatures to a PDF document](/guides/dotnet/csharp/editor/add-visible-signature-to-pdf.md) - [Advanced digital signature workflows](/guides/dotnet/csharp/editor/advanced-digital-signatures.md) - [Detecting and adding form fields to a PDF document](/guides/dotnet/csharp/editor/detect-and-add-form-fields.md) - [Editing PDF form fields](/guides/dotnet/csharp/editor/editing-pdf-form-fields.md) - [Editing PDF metadata with Nutrient .NET SDK](/guides/dotnet/csharp/editor/editing-pdf-metadata.md) - [Filling PDF form fields](/guides/dotnet/csharp/editor/fill-pdf-form.md) - [Managing PDF page order](/guides/dotnet/csharp/editor/manage-pdf-page-order.md) - [Merging PDFs](/guides/dotnet/csharp/editor/merge-pdf-into-other-pdf.md) - [Nutrient .NET SDK extraction guides](/guides/dotnet/csharp/extraction.md) - [Applying OCR to a PDF page](/guides/dotnet/csharp/extraction/apply-ocr-to-pdf-page.md) - [Applying OCR to a PDF document](/guides/dotnet/csharp/extraction/apply-ocr-to-pdf.md) - [Classifying documents](/guides/dotnet/csharp/extraction/classify-document.md) - [Generating image descriptions using Claude](/guides/dotnet/csharp/extraction/describe-image-with-claude.md) - [Generating image descriptions using local AI](/guides/dotnet/csharp/extraction/describe-image-with-local-ai.md) - [Generating image descriptions using OpenAI](/guides/dotnet/csharp/extraction/describe-image-with-openai.md) - [Detecting document language](/guides/dotnet/csharp/extraction/detect-document-language.md) - [Extracting data from images using ICR](/guides/dotnet/csharp/extraction/extract-data-from-image-icr.md) - [Extracting data from images using OCR](/guides/dotnet/csharp/extraction/extract-data-from-image-ocr.md) - [Extracting data from images using vision language models](/guides/dotnet/csharp/extraction/extract-data-from-image-vlm.md) - [Extracting data from specific pages](/guides/dotnet/csharp/extraction/extract-data-from-specific-pages.md) - [Extracting form fields from images](/guides/dotnet/csharp/extraction/extract-form-fields-from-image.md) - [Extracting structured data from documents](/guides/dotnet/csharp/extraction/extract-structured-data.md) - [Generating extraction schemas](/guides/dotnet/csharp/extraction/generate-extraction-schema.md) - [Extracting JSON data from a PDF document](/guides/dotnet/csharp/extraction/json-data-extraction.md) - [Labeling form fields with a vision language model](/guides/dotnet/csharp/extraction/label-form-fields-with-vlm.md) - [Parsing a document into structured content](/guides/dotnet/csharp/extraction/parse-document.md) - [Extracting text from PDF documents](/guides/dotnet/csharp/extraction/pdf-to-text.md) - [Reading barcodes with vision extraction](/guides/dotnet/csharp/extraction/read-barcodes-with-vision.md) - [Extracting text from multilingual images](/guides/dotnet/csharp/extraction/read-text-from-image-multi-language.md) - [Extracting text from images](/guides/dotnet/csharp/extraction/read-text-from-image.md) - [Searching document text](/guides/dotnet/csharp/extraction/search-document-text.md) - [Speeding up first ICR operation by predownloading models](/guides/dotnet/csharp/extraction/speed-up-first-icr-by-downloading-requirements.md) - [Nutrient .NET SDK template guides](/guides/dotnet/csharp/templates.md) - [Word template generation and processing](/guides/dotnet/csharp/templates/word-template-generation.md) - [Word template processing-to-PDF/UA conversion](/guides/dotnet/csharp/templates/word-template-to-pdf-ua.md) - [Nutrient .NET SDK troubleshooting guides](/guides/dotnet/csharp/troubleshooting.md) - [Handling errors](/guides/dotnet/csharp/troubleshooting/error-handling.md)