Inspect PDF Page Boxes - Free Online Browser Tool

Read MediaBox, CropBox, TrimBox, BleedBox and ArtBox without changing the PDF.

A PDF can look correct on screen while carrying a wrong crop, bleed or trim box for print production. This read-only inspector reports the effective page geometry in points and millimetres, compares boxes across pages, and flags mixed sizes or boxes that fall outside the MediaBox.

This inspect pdf page boxes utility runs completely inside your web browser. Your document is opened locally and processed on your own device using JavaScript and WebAssembly, so your file is never uploaded to any server. There is no signup, no watermark and no limit on how many documents you can handle.

  • 100% client-side - files never leave your device
  • Instant processing, no upload wait
  • Works on desktop, tablet and mobile
  • Free forever, no account required

Common next steps: Inspect Page Dimensions, Standardize Page Sizes, Add Printer Crop & Trim Marks, Add 3mm / 5mm Bleed Margin.

How to Use the Inspect PDF Page Boxes Tool

Four steps, and the whole thing runs locally on your own device.

  1. Select a PDF

    The document is read locally and each page is inspected without rewriting its bytes.

  2. Review page geometry

    See width, height, orientation and rotation for every page, plus each available PDF page box.

  3. Check print warnings

    Mixed page sizes, missing boxes, invalid nesting and inconsistent box dimensions are listed explicitly.

  4. Export the report

    Download JSON for automation, CSV for spreadsheets or readable text for a print handoff.

Frequently Asked Questions

What is the MediaBox?

MediaBox is the physical page boundary. Other boxes such as CropBox, TrimBox and BleedBox describe how the page is displayed or prepared for print.

Does this change my PDF?

No. The tool is read-only and does not save or modify the source PDF.

Why are some boxes unavailable?

Optional boxes may not exist in the file, may be inherited in an unsupported structure, or may be unreadable in an encrypted PDF. The report says unavailable rather than inferring them.

What does a mixed-size warning mean?

It means effective page dimensions differ across the document, which can affect printing, imposition, booklet creation or submission requirements.

Are points converted to millimetres exactly?

The report uses the standard 72 points per inch and 25.4 millimetres per inch conversion, rounded for readability.