PDF.js vs PDF.js Express

Compare out-of-the-box features between PDF.js and PDF.js Express. PDF.js is an open-source PDF library that was created by Mozilla in 2011 to let you open and render PDFs in web browsers using JavaScript. PDF.js Express is a fully-featured commercial PDF.js viewer with a modern and customizable UI

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PDF.jsPDF.js Express


Multiple display modes (fit to page, fit to width, full screen)checkcheck
Page transitions (continuous, page by page)checkcheck
Layout (single, double, cover)checkcheck
See thumbnailscheckcheck
See document outline and bookmarkscheckcheck
Print documentscheckcheck
Full localization supportcheckcheck


Collaborate in real-timecheck
Freehand, free text, shape, comment annotationscheck
Stamp document with text, imagescheck
Watermark to prevent distributioncheck
User roles and permissions (control access to each annotation)check
Annotation events to trigger custom functionalitycheck
Measurement toolscheck
Create custom annotationscheck

Modern UI

Fully responsive UIcheck
Customizable UIcheckcheck
UI written in React.JScheck
UI Source code downloadablecheckcheck
Dark Themecheckcheck
Hide/Show Download/Print and other toolscheckcheck


User form fillingcheck
Merging form datacheck
Programmatically prepopulate formscheck
Extract forms data and save values separatelycheck
JavaScript field validation/formattingcheck
Customize form appearancecheck


Sign by using hand-drawn annotationcheck
Save signatures for signing multiple pagescheck


Multiple search optionscheck
Ambient string, return context to your searchcheck


Rendering engine

Open-source community

Open-source community

PDF Viewer

Open-source community

1-on-1 support



PDF.js Express

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