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PDF.js Express Free Viewerplay_arrow

Professional PDF.js Viewing - Free

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Professional PDF.js Viewing & Annotations - Try for free

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Common use cases

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Open a document

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Save a document

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Viewer

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UI Customization

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Annotations

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Collaboration

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Forms

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Signature

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Measurement

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Advanced Capabilities

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PDF.js Express REST API

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Migration Guides

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MIME types

The following features are available in:

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PDF.js Express Viewer

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PDF.js Express Viewer is a free viewer with limited capabilities compared to PDF.js Express Plus

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PDF.js Express Plus

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PDF.js Express Plus is a commercial PDF SDK for viewing, annotating, signing, form filling and more

If you see a 404 for files on your server but you're very sure that the files are there then you may need to set MIME types for certain file extensions used by WebViewer. With IIS you will generally need to do this and the process may vary slightly depending on your server.

Regardless of the documents that you're loading you'll need to add the MIME type for json files (application/json) so that the UI text is loaded. If you see buttons or labels in the UI with names like controlbar.fullScreen then that means the json file wasn't loaded successfully.

XOD

You'll need to add xod with a MIME type of application/octet-stream or application/vnd.ms-xpsdocument

PDF and Office

ExtensionMIME Type
resapplication/octet-stream
pexeapplication/x-pnacl
nmfapplication/octet-stream
memapplication/octet-stream
wasmapplication/wasm
jsonapplication/json