Open Source Document Processing APIs Guide

Learn about open source APIs and libraries to view, edit, convert, annotate, compare, sign, assemble, search, parse, merge, watermark, redact and classify documents.

Get Started with Document Processing APIs

Document Processing APIs with Examples

A collection of open source APIs for processing documents (DOC, DOCX, XLS, XLSX, PDF, etc.) that application developers can use in different programming languages such as Javascript, Python, PHP and many more.

Document Viewer


Explore free and open source APIs to view and render documents like PDF, Word, and Excel across different platforms.

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Document Editor


Create and edit widely used document formats like PDF, DOC/DOCX, Spreadsheets & Images etc. on different platforms using open source document editor libraries.

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Document Annotation


Add interactive comments, markups and annotations on PDFs and images with the help of cross-platform open-source libraries.

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Document Conversion


Discover open-source document conversion libraries that facilitate effortless transformation of commonly used formats like PDF, DOC, DOCX, XLS, XLSX, images, and more into other formats.

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Document Merger


Explore free and open source document merger libraries that allow joining, splitting, rotating, swapping and deleting pages etc. of commonly used formats like PDF, DOC/DOCX and more.

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Document Parser


Read, parse and extract text, images and other information from popular document formats like PDF, DOC/DOCX, XLS/XLSX and more using open source document parser libraries on different platforms.

Explore Document Parser APIs