Build Better Apps Faster with Kdan PDF SDK

Elevate your application with Kdan PDF SDK. Seamlessly integrate features like PDF creation, reading, page and text editing, signing, annotation, encryption, document comparison, OCR, and watermarking across mobile, desktop, web, and server platforms.


Developing with the #1 Mobile PDF Solution

Kdan PDF SDK enhances your application's capabilities by integrating a suite of professional and comprehensive functions. Offering compatibility with a wide range of programming languages, Kdan PDF SDK seamlessly deploys on local PDF SDK, PDF API, and on-premise servers.

Windows PDF Library

With C#, C/C++, Python, Java, ASP.NET, ASP.NET Core, VB.NET libraries, ComPDFKit allows you to easily and quickly integrate PDF functionality like viewing, annotating, form filling, signing, and document editing into your Windows applications.

Web PDF Library

With JavaScript, TypeScript and C/C++ libraries, ComPDFKit allows you to easily and quickly integrate PDF functionality like viewing, annotating, form filling, signing, and document editing into your Web applications. Support for all browsers (Chrome, Edge, Firefox, Safari, etc.) and major web frameworks (Electron, Vue, Nuxt, React, Next, Svelte, Angular, ionic angular, etc.).

Android PDF Library

With Kotlin, Java, and C/C++ libraries, ComPDFKit allows you to easily and quickly integrate PDF functionality like viewing, annotating, form filling, signing, and document editing into your Android applications.

iOS PDF Library

With Objective-C, Swift, and C++ libraries, ComPDFKit allows you to easily and quickly integrate PDF functionality like viewing, annotating, form filling, signing, and document editing into your iOS applications.

Mac PDF Library

By leveraging Objective-C, Swift, and C++ libraries, ComPDFKit empowers you to seamlessly and efficiently incorporate advanced PDF features into your Mac applications. This encompasses tasks such as viewing, annotating, form filling, signing, and editing documents.

Server PDF SDK Library

Deliver dependable solutions for server platforms, including Java, .NET Core, Python, PHP, C/C++, Processor, and command-line tools, facilitating the seamless processing of PDF files. Multi-threaded and distributed environments are supported. Realize essential PDF functions, such as generation, viewing, editing, document comparison, OCR, conversion, and more, within server applications.

Flutter PDF SDK

Use the professional Flutter library to integrate PDF functionality into your iOS and Android apps, enjoy Flutter's flexible development experience, high performance, and beautiful interface, and realize PDF preview, editing, signing, cipher marking, annotating, and other functions.

React Native PDF SDK

Incorporate our professional cross-platform PDF SDK solution. Empower your users to view, edit, annotate, convert formats, redact, merge, split, fill out, and encrypt PDF files.


Professional HTTP API allows you to easily and quickly integrate PDF functionality into applications across all development platforms without worrying about the compatibility of programming languages with the API. Supports remote invocation and private deployment.

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The Comprehensive PDF Kit

Kdan's PDF SDK has all the functionality you need. Developers can leverage the power of PDF SDK advantages in your applications.


Kdan PDF SDK presents a robust reading engine, ensuring stable and swift opening, even for large files. It encompasses theme modes, navigation, search, magnification, page-turning effects, bookmarks, outlines, and more.


Empower your application to add and edit annotations, including markups, shapes, free text, notes, ink, stamps, links, sound recordings, and more. Kdan PDF SDK is fully compliant with PDF specifications and is compatible with other PDF software.

Edit PDF Content

The PDF editing SDK addresses the demands of PDF editing, providing robust support for adding, deleting, editing, and moving PDF texts, images, and pages.

Fill Forms

Create fillable forms for receipts, contracts, and tax documents effortlessly with Kdan PDF SDK. The SDK offers a variety of tools, including text fields, drop-down lists, table borders, checkboxes, buttons, and signatures.


Incorporating with the signing SDK, users can insert signatures or collect signatures from others. The SDK supports electronic and digital signatures, meeting diverse signing requirements.

PDF Security

The Kdan PDF SKD provides standard encryption with RC4 and advanced algorithms AES-128 & AES-256 to cater to the diverse security needs of your projects. The SDK delivers encryption, decryption, permission settings, Bates numbering, headers and footers, and more.


Effortlessly overlay and irrevocably remove sensitive or confidential text or images from PDF documents. Support the customization of style, color, and explanatory text for redactions.

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Seamless Integration with Kdan PDF SDK

Kdan PDF SDK is easy to integrate with a few lines of code.

Viewing a PDF
Creating an annotation
#import <ComPDFKit/ComPDFKit.h> // Load a document. // This is the container for your PDF file. It can also manage multiple files. NSBundle *bundle = [NSBundle mainBundle]; NSString *pdfPath= [bundle pathForResource:@"Test" ofType:@"pdf"]; NSURL *url = [NSURL fileURLWithPath:pdfPath]; CPDFDocument *document = [[CPDFDocument alloc] initWithURL:url]; // Initialize a CPDFView object with the size of the entire screen. CGRect rect = [[UIScreen mainScreen] bounds]; CPDFView *pdfView = [[CPDFView alloc] initWithFrame:rect]; pdfView.document = document;

Powered by Kdan PDF SDK


ibon is designed for connecting ibon cloud printing service. With Kdan PDF SDK integration, the ibon app enables users to preview files before they upload files to ibon cloud. Then they can go to any 7-11 store to print the documents without spending time checking files when using the actual machine.

Taiwan Intellectual Property Office (TIPO)

Taiwan Intellectual Property Office (TIPO) is an administrative agency responsible for IP policy formulation, IP laws drafting, and inter-agency enforcement coordination. TIPO integrates Kdan's PDF SDK with their intranet document system where the employees can review and edit PDF documents for patent applications, including invention, utility model, and design patents.


DottedSign is a cloud-based e-sign service. Integrated with Kdan PDF SDK, its iOS and Android apps allow users to facilitate PDF viewing and editing functionalities. Users can add signatures, text and stamps onto PDF documents right from their smart devices.


Want to test Kdan PDF SDK out?

Contact our sales team for more information or request a free trial.