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PDF Page Size Checker

Check whether a PDF is A4, US Letter, Legal or a mix, with exact dimensions in millimetres, inches and points for every size group. Free and private.

Drop a PDF here or click to browseDetects A4, Letter, Legal and mixed page sizes

What is the PDF Page Size Checker?

The ByteTools PDF Page Size Checker answers one question fast: what size are the pages in this PDF? It measures every page, groups the identical ones, names the paper format it matches, and gives you the exact dimensions in millimetres, inches and PDF points.

  • Instant A4 / Letter / Legal / A3 / A5 / Tabloid detection
  • Clear verdict on whether the document is consistent
  • Dimensions in millimetres, inches and PDF points
  • Groups pages by size and lists them as compact ranges
  • Rotation-aware, so sizes match what you see on screen
  • Runs entirely in your browser — no upload required

How to use the PDF Page Size Checker

  1. 1

    Drop a PDF onto the upload area.

  2. 2

    Read the verdict banner: a single consistent size, or a mixed document.

  3. 3

    Check the table for each size in millimetres, inches and points.

  4. 4

    Use the page list to find exactly which pages differ, then copy the report.

About the PDF Page Size Checker

The ByteTools PDF Page Size Checker answers one question fast: what size are the pages in this PDF? It measures every page, groups the identical ones, names the paper format it matches, and gives you the exact dimensions in millimetres, inches and PDF points.

The file is measured in your browser and never uploaded. Print-ready artwork, tender packs and scanned bundles can be verified privately before you send them to a printer or a portal.

It is the quickest way to catch a mixed-size document — the classic cause of a print job that comes back with some pages shrunk. If the sizes are inconsistent, the report tells you exactly which pages are the odd ones out.

Frequently asked questions

How do I check if a PDF is A4 or Letter?

Drop the file into this checker and read the banner at the top. A4 measures 210 × 297 mm (595 × 842 points) and US Letter measures 216 × 279 mm (612 × 792 points), and the tool names whichever one your pages match — or tells you they are a custom size.

Why does my PDF have mixed page sizes?

Usually because it was assembled from different sources — a Letter-size cover merged with A4 body pages, or a landscape spreadsheet inserted into a portrait report. Scanners set to auto-detect paper also produce slightly different sizes per page.

Do mixed page sizes cause printing problems?

Often, yes. Printers apply a single paper setting to the whole job, so odd-sized pages get scaled or clipped. Running the file through the Resize PDF tool first normalises everything onto one sheet size.

What are PDF points and why are they used?

A point is 1/72 of an inch and is the native unit of the PDF format. It comes from traditional typography, which is why page sizes are stored as 595 × 842 for A4 rather than in millimetres.

Why is my page size a few points off the standard?

A4 is 595.28 points wide, so files rounded to 595 or 596 are still A4. This checker allows a small tolerance and names the paper anyway. Bigger differences usually mean a custom size or a scan that was cropped.

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