--- title: "PdfConformance" canonical_url: "https://www.nutrient.io/api/csharp/enums/pdf-conformance/" md_url: "https://www.nutrient.io/api/csharp/enums/pdf-conformance.md" last_updated: "2026-10-08T08:55:57.709Z" description: "Specifies PDF versions and conformance levels of a PDF document. The PDF versions correspond to the PDF major releases, starting from PDF 1.0." --- Specifies PDF versions and conformance levels of a PDF document. The PDF versions correspond to the PDF major releases, starting from PDF 1.0. In each PDF version the new features have been introduced. The different conformance levels reflect the quality of the archived document and depend on the input material and the documents purpose. PDF/A versions and levels are given one after another. PDF/A-1 is the first archiving standard based on PDF version 1.4. All resources must be embedded within the PDF/A document itself. PDF/A-2 is based on PDF 1.7. It allows JPEG2000 compression, transparent elements, PDF layers and more. PDF/A-3 is available since October 2012. It allows to embed any file format desired. Level a (accessible) meets all requirements for the standard. Level b (basic) guaranteed that the content of the document can be unambiguously reproduced. Level u (unicode) specifies that all text can be mapped to standard Unicode character codes. ```csharp using Nutrient; ``` ## Values | Name | Value | Description | | ------------------------- | ----- | ------------------------------------------------------------------------------ | | `PdfConformance.PDF` | `0` | This is a common PDF document. Read more about PDF compatibility levels here. | | `PdfConformance.PDF_A_1a` | `1` | The PDF conformance level is PDF/A-1a. | | `PdfConformance.PDF_A_1b` | `2` | The PDF conformance level is PDF/A-1b. | | `PdfConformance.PDF_A_2a` | `3` | The PDF conformance level is PDF/A-2a. | | `PdfConformance.PDF_A_2u` | `4` | The PDF conformance level is PDF/A-2u. | | `PdfConformance.PDF_A_2b` | `5` | The PDF conformance level is PDF/A-2b. | | `PdfConformance.PDF_A_3a` | `6` | The PDF conformance level is PDF/A-3a. | | `PdfConformance.PDF_A_3u` | `7` | The PDF conformance level is PDF/A-3u. | | `PdfConformance.PDF_A_3b` | `8` | The PDF conformance level is PDF/A-3b. | | `PdfConformance.PDF_A_4` | `9` | The PDF conformance level is PDF/A-4. | | `PdfConformance.PDF_A_4e` | `10` | The PDF conformance level is PDF/A-4e. | | `PdfConformance.PDF_A_4f` | `11` | The PDF conformance level is PDF/A-4f. | | `PdfConformance.PDF1_0` | `12` | The PDF version is PDF 1.0. | | `PdfConformance.PDF1_1` | `13` | The PDF version is PDF 1.1. | | `PdfConformance.PDF1_2` | `14` | The PDF version is PDF 1.2. | | `PdfConformance.PDF1_3` | `15` | The PDF version is PDF 1.3. | | `PdfConformance.PDF1_4` | `16` | The PDF version is PDF 1.4. | | `PdfConformance.PDF1_5` | `17` | The PDF version is PDF 1.5. | | `PdfConformance.PDF1_6` | `18` | The PDF version is PDF 1.6. | | `PdfConformance.PDF1_7` | `19` | The PDF version is PDF 1.7. | | `PdfConformance.PDF2_0` | `20` | The PDF version is PDF 2.0 (ISO 32000-2). | | `PdfConformance.PDF_UA_1` | `21` | The PDF conformance level is PDF/UA-1. | | `PdfConformance.Unknown` | `-1` | The PDF conformance level is unknown. | --- ## Related pages - [Enums](/api/csharp/enums.md) - [Auto Tagging Engine](/api/csharp/enums/auto-tagging-engine.md) - [Description Level](/api/csharp/enums/description-level.md) - [Document Bookmark Source](/api/csharp/enums/document-bookmark-source.md) - [Document Format](/api/csharp/enums/document-format.md) - [Document Markup Mode](/api/csharp/enums/document-markup-mode.md) - [Document Type](/api/csharp/enums/document-type.md) - [Execution Provider](/api/csharp/enums/execution-provider.md) - [Form Vlm Enrichment Model](/api/csharp/enums/form-vlm-enrichment-model.md) - [Html Layout Type](/api/csharp/enums/html-layout-type.md) - [Image Export Format](/api/csharp/enums/image-export-format.md) - [Image Export Mode](/api/csharp/enums/image-export-mode.md) - [Image Setting Mode](/api/csharp/enums/image-setting-mode.md) - [Implicit Conversion](/api/csharp/enums/implicit-conversion.md) - [Inline Style Reference Mode](/api/csharp/enums/inline-style-reference-mode.md) - [Instant Json Render Theme](/api/csharp/enums/instant-json-render-theme.md) - [Json Export Content](/api/csharp/enums/json-export-content.md) - [Json Export Format](/api/csharp/enums/json-export-format.md) - [Ocr Activation Mode](/api/csharp/enums/ocr-activation-mode.md) - [Ocr Engine](/api/csharp/enums/ocr-engine.md) - [Open Settings Mode](/api/csharp/enums/open-settings-mode.md) - [Page Cache Mode](/api/csharp/enums/page-cache-mode.md) - [Paper Normalization Mode](/api/csharp/enums/paper-normalization-mode.md) - [Pdf Border Style](/api/csharp/enums/pdf-border-style.md) - [Pdf Compression](/api/csharp/enums/pdf-compression.md) - [Pdf Form Field Type](/api/csharp/enums/pdf-form-field-type.md) - [Pdf Line Ending Style](/api/csharp/enums/pdf-line-ending-style.md) - [Pdf Page Sizes](/api/csharp/enums/pdf-page-sizes.md) - [Pdf Rubber Stamp Icon](/api/csharp/enums/pdf-rubber-stamp-icon.md) - [Pdf Save Preferences](/api/csharp/enums/pdf-save-preferences.md) - [Pdf Settings Mode](/api/csharp/enums/pdf-settings-mode.md) - [Pdf Validation Conformance](/api/csharp/enums/pdf-validation-conformance.md) - [Rendering Layout Mode](/api/csharp/enums/rendering-layout-mode.md) - [Restoration Mode](/api/csharp/enums/restoration-mode.md) - [Schema Compatibility](/api/csharp/enums/schema-compatibility.md) - [Search Display](/api/csharp/enums/search-display.md) - [Search Mode](/api/csharp/enums/search-mode.md) - [Signature Certification Level](/api/csharp/enums/signature-certification-level.md) - [Signature Format](/api/csharp/enums/signature-format.md) - [Signature Hash Algorithm](/api/csharp/enums/signature-hash-algorithm.md) - [Signature Key Source](/api/csharp/enums/signature-key-source.md) - [Signature Level](/api/csharp/enums/signature-level.md) - [Text Direction](/api/csharp/enums/text-direction.md) - [Tiff Compression](/api/csharp/enums/tiff-compression.md) - [Unit Mode](/api/csharp/enums/unit-mode.md) - [Unparseable Output Handling](/api/csharp/enums/unparseable-output-handling.md) - [Vision Engine](/api/csharp/enums/vision-engine.md) - [Vision Features](/api/csharp/enums/vision-features.md) - [Vision Output Format](/api/csharp/enums/vision-output-format.md) - [Vlm Classification Strategy](/api/csharp/enums/vlm-classification-strategy.md) - [Vlm Provider](/api/csharp/enums/vlm-provider.md) - [Word Refining Method](/api/csharp/enums/word-refining-method.md)