PDF Page Size Inspector
See every PDF page size, orientation and paper name.
How to use
- 1 Drop a PDF onto the box, or click to choose one.
- 2 Read the per-page table of width, height, orientation and paper.
- 3 Switch units between mm, inches and points as needed.
- 4 Click Download CSV to save the full report.
About PDF Page Size Inspector
PDF Page Size Inspector opens a PDF and tells you exactly how big each page is.
Drop in a file and it lists every page with its width and height, its orientation, and a best-guess paper name such as A4, A5, US Letter or US Legal — switchable between millimetres, inches and raw PDF points.
A one-line summary tells you instantly whether the document is uniform or a mix of sizes.
This is the diagnostic step that saves a botched print run.
Before sending a file to a printer, a binder or a colleague, you can confirm it is genuinely A4 and not a near-miss custom size, spot the one landscape page hiding in a portrait report, or catch the oversized cover that will jam a desktop printer.
Designers use it to verify trim sizes; anyone merging documents from different sources uses it to find the odd page out before things go wrong.
Sizes are read from each page media box using pdf-lib, and common paper formats are matched in either orientation within a small tolerance, so a slightly rounded A4 still reads as A4.
You can export the full table as a CSV for a print checklist or a bug report.
Everything runs locally in your browser — the PDF is parsed in memory and never uploaded — so even confidential documents stay on your device, and it keeps working offline once the page has loaded.
FAQ
How is the paper size detected?
Each page is measured in millimetres and matched against common formats (A3–A6, US Letter, Legal, Tabloid) in either orientation within a 2 mm tolerance. Anything that does not match is labelled Custom.
Is my PDF uploaded?
No. Page sizes are read with pdf-lib entirely in your browser, so the document never leaves your device.
Why do some sizes look slightly off?
PDF dimensions are stored in points (1/72 inch) and often carry tiny rounding. The tool rounds for display and matches paper sizes within a small tolerance.