Best Free PDF SDK of 2025

Pdftools can help you process thousands of documents, or even millions. The suite of SDKs from Pdftools is designed for industries that are document-intensive. They will make your document workflows faster, easier, and less stressful. The Pdftools products are built on SDKs or APIs. They integrate seamlessly with your existing systems and applications. Process thousands of documents per minute. Our tools are designed to be fast and efficient. We are engineers at heart and only accept the most reliable, usable and well documented platforms. File sizes can be reduced, but quality and interactivity are not compromised. Your documents will be compliant with long-term archiving. We have documented every detail of our products so that you can easily get started.

Global OEMs, SaaS and enterprise end-users rely on Adobe PDF Library to automate the creation, editing and management of PDFs. An Adobe partner, our SDK uses the same source code as Acrobat for stability, reliability and quality results. Languages: .NET, .NET Framework, Java and C/C++ Platforms: Windows, Linux & MacOS Package managers: NuGet & Maven Capabilities include but are not limited to: -Annotations -Content creation -Content modification -Color management -Extraction - text, images, forms -Compression/optimize -Conversion - PDF/A, PDF/X, EPS, PostScript, XPS, ZUGFeRD, color -Display, Printing -Extract text, images & other content -Forms - Import, export, flatten static & dynamic XFA forms, AcroForms -Images - extract, import/export, thumbnails, render/rasterize pages, separations -Optimization - size, content, images, etc. -OCR - add text to document, add text to image -PDF to Office Documents (Word, Excel, PPT) -Security - Viewer settings, redactions, password, encrypt/decryption, watermark Pricing options for OEMs, SaaS & end-users are flexible and based on usage. Shorten development times & get to market faster with Adobe PDF Library. Free trial - download today.

pdfRest API Toolkit was made by developers, for developers. Rapidly integrate PDF workflows with your business applications, simply and seamlessly. pdfRest API Toolkit includes all the PDF processing tools you'll need, designed and developed by digital document experts with decades of experience to make your job easy: PDF to Word, PDF to Excel, PDF to PowerPoint, Add to PDF, Extract Text, Query PDF, Convert to PDF, PDF to Images, Convert to PDF/A, Convert to PDF/X, Compress PDF, Linearize PDF, Flatten Forms, Flatten Transparencies, Flatten Annotations, Flatten Layers, Merge PDFs, Split PDF, Encrypt PDF, Decrypt PDF, Restrict PDF, Watermark PDF, Import Form Data, Export Form Data, OCR PDF, Upload Files, Zip Files. Clear documentation with intuitive endpoints and parameters. Start with sample code in .NET, JavaScript, Python, PHP, and cURL for every endpoint. Gold-standard processing powered by Adobe® PDF Library™. Free to get started with no commitment. Affordable pricing for projects of all sizes. pdfRest was designed for developers, by developers to make working with PDFs as easy and intuitive as possible. Flexible APIs can be called from any language capable of making an API request. Send your first API call in

KDAN PDF Reader is your all-in-one PDF solution. Edit, sign, OCR scan, convert, annotate, and fill forms in PDF documents. With innovative AI features, speed up your document workflow! Designed for Mac, iPhone, and iPad, KDAN PDF Reader is trusted by millions for its comprehensive features and efficiency. KEY FEATURES EDIT TEXT & PDF • Fix errors and typos directly in PDF - replace, add, or delete text in PDFs • Add, edit, crop, and adjust images in PDFs • Add header & footer • Add Bates numbering for easy reference, tracking, and organization • Use stamps or dynamic stamps to indicate status, provide feedback, and highlight information in a document CONVERT PDF • Offline file converter - convert file without an internet connection • Convert PDF to Office file formats, image, or ePub • Format supported- docx, xlsx, csv, pptx, rtf, txt, html, jpg, png, BMP, jpg200, pub, MOBI SIGN & FORMS • Fill & edit forms • Create fillable forms with buttons, checkboxes, and list boxes • Create signature and sign on PDF • Create signatures using trackpad, keyboard, or images EDIT PAGE • Merge & split PDFs • Extract, rearrange, rotate, delete, and crop PDF pages • Change PDF background color • Append pages from

ComPDFKit offers a top-quality PDF SDK, PDF API, and PDF Server for companies, organizations, small businesses, and developers. It enables you to integrate PDF document annotation, editor, conversion, form filling, and signing into your applications or products, saving you time and expenses. ComPDFKit is compatible with Windows, Web, Android, iOS, Mac, Linux, and other cross-platform frameworks such as React Native, Flutter, and Electron with just a few lines of code. ComPDFKit Updates: 1. ComPDFKit API Sign up and Get 1000 Free Files Processing Monthly. Allow you to edit & convert PDF files, split/merge/insert/rotate/delete/extract PDF pages, and process PDFs with OCR. 2. Free Online Tools Work with PDF in ComPDFKit online PDF tools to convert PDF files to/from docx, xlsx, pptx, png, jpg, html, txt, csv, rtf files, etc. 3. Web Demo View, Edit, Annotate, Compare, Sign, Encrypt, Decrypt, watermark PDF files, and Create/fill out PDF forms online for free. 4. Community License Start-ups and Individual developers can get affordable prices from ComPDFKit. We help you to build your customized applications with a special price and discount.

AmindPDF's user interface is very user-friendly and makes the operation of PDF easy. It can recognize PDF text as paragraphs or whole blocks of text, allowing users to edit text directly and smoothly, like in MS Word. for PDF protection, it allows adding passwords, setting document permissions, placing signatures, adding watermarks to PDF. It also supports batch operations to process files, such as merge/split tool, compression tool, creation tool, Bates numbering tool, and conversion tool, so users can process multiple PDF files at once. AmindPDF is available for a number of platforms: Windows, iOS, and Android. Users are able to use the same PDF tool on a computer or mobile phone. So AmindPDF let you process or edit PDFs anytime, anywhere. Edit PDF Text: AmindPDF allows the user to change the font, font size, font color, and font style, and reset the alignment of pdf text. Edit Images: The user can select the images in pdf, then manipulate the images: replace an image, rotate the image, crop the image, or remove the image. AmindPDF can combine more than one PDF or image file into one PDF. The file name of being combined files will be used to build the outline of the combined pdf.

Anvil offers businesses that need to handle a large number of PDFs—whether for filling, generating, maintaining, or signing—a flexible and customizable workflow platform that is embedded and driven by logic. This solution allows organizations to efficiently manage their document processes while ensuring a streamlined user experience.

FPDF is a PHP-based tool that enables the creation of PDF files directly through PHP, making it an alternative to the PDFlib library. The acronym FPDF stands for "free," indicating that it can be utilized and customized without restriction to meet various user requirements. This library functions without the need for additional PHP extensions, aside from Zlib for compression and GD for GIF functionality, and is compatible with PHP versions 5.1 and later, including PHP7 and PHP8. With a range of tutorials available, users can quickly learn to navigate FPDF effectively. Notably, FPDF supports the generation of documents in multiple languages beyond just Western European scripts, accommodating Central, Cyrillic, Greek, and Baltic languages, provided there are suitable TrueType or Type1 fonts available. Additionally, it offers support for UTF-8 encoding. While the document generation speed may not match that of PDFlib, it is still quite reasonable and sufficient for most applications unless specific document precision is required. This versatility makes FPDF a popular choice among developers looking for a straightforward PDF generation solution.

pdfToolbox provides robust and flexible PDF processing capabilities that are seamlessly integrable, allowing for both quick visual inspections and fully automated handling of large volumes of files. Leveraging reliable Adobe technology, pdfToolbox effectively addresses and resolves even the most intricate issues, facilitates color management, supports imposition, and allows for conversion to and from PDF formats. This technology is widely utilized by a diverse range of users including small businesses, major publishing houses, and print service providers, along with OEMs who incorporate it into their own offerings. The Desktop version of pdfToolbox serves as a manual PDF preflight and correction tool, available either as a plug-in for Adobe Acrobat Pro or as a standalone application. Designed with prepress operators in mind, pdfToolbox provides an intuitive interface for all pre-press tasks, enabling users to access any necessary function in just three straightforward steps. Furthermore, users can personalize the setup to ensure that their most frequently used actions are always readily accessible. This level of customization enhances productivity and streamlines the workflow for professionals in the print industry.

PDFlib GmbH dedicates itself entirely to advancing PDF technology, with customers utilizing its products since 1997. In 2006, the company became a founding member of the PDF Association (previously known as PDF/A Competence Center). The organization keeps a close eye on industry developments and market trends, including adherence to ISO standards for PDF. PDFlib GmbH's offerings are available globally, with significant market presence in Europe, North America, and Japan. As a well-known developer component, PDFlib specializes in generating and manipulating PDF documents effectively. Its primary objectives include the dynamic generation of PDFs on web servers, as well as in various server, desktop, or mobile applications. By using PDFlib, users can dynamically produce PDF documents sourced from databases, akin to creating dynamic web pages. Since its inception in 1997, PDFlib has demonstrated its versatility across a broad spectrum of use cases and development ecosystems. Application developers leverage PDFlib to generate PDF outputs that incorporate text, images, graphics, and interactive features, making it an essential tool in modern document creation. With its robust capabilities, PDFlib continues to be a favorite among programmers seeking effective PDF solutions.

Vanilla.PDF is a PDF toolkit that's easy to use and has the most power. The framework supports all PDF formats, PAdES electronic signings, including PKCS#11 interface. A well-documented interface with fully-featured examples assures that the results meet the highest market standards. For any questions, please don't hesitate to contact us!