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PDF.js-based Page Inspector

PDF Inspect

Preview PDF page by page and inspect the fonts, images, and instruction stream structure of the current page. All analysis is completed locally in the browser.

Security and Privacy Commitment

All operations are completed locally in your browser—files are never uploaded to any server, ensuring your data remains absolutely secure.

Drag a PDF here, or click to select a file

Supports page-by-page preview, viewing document metadata, and analyzing fonts, images, and operator tree of the current page.

How to Use PDF Inspect

1

Import PDF

Drag the file into the page. The tool will read the document metadata and prepare the first page for analysis.

2

Switch Pages

Quickly navigate through multi-page documents using the previous page, next page, and page number input box.

3

View Resources and Instructions

Switch between Overview, Fonts, Images, and Instruction Stream tabs to inspect the PDF's internal structure page by page.

Why use this tool to inspect PDFs

Page-focused

Instead of traversing the entire document at once, view the current page's resources and instructions first to pinpoint issues faster.

Directly visualize the drawing process

Organizes pdf.js's operator list into a structured tree, making it easier to understand how a page is rendered step by step.

Local analysis

Files are not uploaded to the server, making it ideal for inspecting contracts, reports, and internal documents.

Ideal for troubleshooting resource issues

Quickly verify which fonts and images are actually used on the current page and whether they are properly embedded.

Frequently Asked Questions

Will the files be uploaded?
No. PDF loading, preview, and resource analysis are all completed locally in the browser.
Why don't some images have thumbnails?
Objects returned by pdf.js are sometimes only suitable for rendering pages, and cannot always be reliably converted into independent thumbnails. The tool will attempt to display decoded bitmap previews whenever possible.
Will this 100% restore the underlying semantics of the PDF?
No. The instruction tree is a semantically organized result designed for reading and troubleshooting, making it easier to understand the sequence of operations that pdf.js processes.
Why might encrypted PDFs not open?
If a PDF requires a password to read and the current page does not provide one, pdf.js cannot complete parsing, and the tool will display a loading failure message.

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