Foxit PDF SDK for Web

Full PDF viewer and editor in your browser using JavaScript. Open, view and annotate PDF files on both mobile and desktop devices. As a purely JavaScript library, our product requires no plug-ins and provides native-like performance no matter where you use it.


Foxit’s first release of 2021 comes with lots of new features and upgrades to our web-based JavaScript web viewer, desktop SDK and mobile SDK.

On the Web SDK side of things, we’ve added a collaboration feature meaning you can now connect multiple clients through a server, webservice or network to the same PDF. Add annotations to a shared file and collaborate in real time with your team for even more efficient document workflows. We’ve also added PDF portfolio support for viewing and downloading PDFs, lots of new form field options as well as major performance enhancements for files with large quantities of annotations.

For our desktop SDK, we’ve added some new APIs to set a DPI limit for image compression, added portfolio support as per the Web SDK above, extended our HTML to PDF conversion to include Linux, along with .TXT to PDF support.

When it comes to mobile, we’ve enhanced the performance of documents containing static XFA forms as well as made improvements to annotation counting, zoom rendering and much more!


Use our PDF library for web applications on mobile on desktop. Integrate with just a few lines of code and customize with a rich API. Fast document rendering, easy navigation, and intuitive annotation tools including highlighting, drawing and notes.
Ink Signatures Android
PDF Page View Android
Form filling Android

PDF Viewing

Our core API provides for high-fidelity rendering of PDF documents with optimized performance for desktop and mobile platforms.

Digital Signature

Use ink signatures to let customers sign documents in their digital devices. Sign PDF in web apps easily without needing to print a file to sign again!

PDF Forms

Give users the ability to fill out digital forms on the go with their device of choice. Apps have never been more productive!
Full Text Search
Strikeout annotation
PDF Password Android

Full-Text Search

Fast full-text search for any PDF document, language, or encoding type. The SQLite-based full-text search delivers near-instant results, even for repositories on any digital device.

PDF Annotations

Our PDF SDK provides full support for displaying and annotating PDF in web applications with an extensive range of functions for creating, editing or importing/exporting annotations.

Text Editing

Foxit’s state-of-the-art text editing functionality enables you to edit already existing text as well as add new text boxes to your PDF documents with just one click.

See it in Action

Have you tried our live demo yet? It includes all the PDF SDK for Web features you can use in your project. View, edit, annotate, secure, and sign PDFs from your browser, regardless of whether you are on a desktop or a mobile!

PDF SDK browser support


PDF SDK for Web is built on the most popular web technologies. 

PDF SDK for Web Languages

JS backend, HTML/CSS/JS frontend

PDF SDK for Web is built on commonly used web technologies to get your programmers up to speed faster, thus reducing time to market.

Client-side Deployment

Some PDF SDKs require to be deployed in a server, severely increasing the cost of use. Foxit PDF SDK for Web operates client-side thus reducing your server hosting costs.

Advanced Technology


XFA Forms are XML-based forms wrapped inside a PDF. Securely capture, present, move, process, output, update and print information associated with static and dynamic XFA forms. Simplify your data sharing, transportation and availability with XFA.

Text Editor

Being able to edit PDF text online is crucial to a lot of business workflows & many JavaScript-based Web Viewers on the market do not offer this functionality. Foxit’s premium text editing feature ensures you can edit & create new text in PDFs with ease.


Leverage our conversion and verification technology to turn regular PDFs into PDF/A compliant documents. If you are already working with PDF/A in your processes, proactively verify third-party PDFs you receive are PDF/A compliant.



Developers can easily design a unique style for their Foxit PDF SDK for Web user interface, and make it consistent to their web app.


Unlike other competitors, Foxit PDF SDK for Web doesn’t have a server-side component, which eliminates the cost of infrastructure.

Easy to Integrate

Developers can easily integrate a PDF viewer in a website by referring to Foxit PDF SDK for Web’s resource files and writing a small amount of code to display and edit PDF files, and have a wealth of interfaces to connect users and user data.

Powered by Foxit’s Powerful Technology

The core technology of PDF SDK for Web is based on Foxit’s PDF rendering engine, which is trusted by a large number of well-known companies. Foxit’s powerful PDF engine makes document viewing fast and consistent in all platforms.


And requires minimal server-side resources!

PDF SDK browser support

Foxit PDF SDK for Web in action

// Add the script below to your javascript file to initialize the viewer
// Replace "window.demoLicenseKey" with your license key
// And replace 'doc' with the path to the PDF file you wish to load

    var docViewerId = 'docViewer';
            var optionsParams = {
                language: window.getLanguage(),
                toolbarConfig: window.toolbarConfig,
                fontUrl: '',
                licenseKey: window.demoLicenseKey,
            WebPDF.ready(docViewerId, options, false).then(function(){
            function openDocument(){
                var fileurl = WebPDF.baseUrl + 'doc';
                var openFileParams = {
                    url: fileurl,
                    fileId: fileurl
WebPDF.ViewerInstance.openFileByUri(openFileParams).catch(function(error) {