PDF Page Size Checker
Check every page's dimensions and spot mixed page sizes before printing.
A PDF assembled from several sources often contains pages of different sizes — an A4 form, a Letter-sized annexure, a Legal-sized certificate. It looks fine on screen and prints badly, with pages scaled inconsistently or content cut off. This checks every page and groups them by size.
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What the PDF Page Size Checker does
PDF measures pages in points, where 72 points is one inch. A4 is 595 × 842 points; US Letter is 612 × 792. They are close enough that the difference is invisible on screen but obvious when printed, because Letter is wider and shorter than A4.
The tool reads each page's dimensions, converts them to millimetres, matches them against standard sizes and reports how many pages fall into each group.
How to use this tool
- Select your PDF. Every page is measured automatically.
- If one size is reported, the document is consistent and will print predictably.
- If several are listed, note which pages differ — they are the ones that will print wrongly.
- Use the page size converter to normalise them before printing.
How sizes are identified
PDF stores page size in points: 72 points = 1 inch
Millimetres = points ÷ 72 × 25.4
Standard sizes, in millimetres:
A3 297 × 420 A4 210 × 297
A5 148 × 210 A6 105 × 148
Letter 216 × 279 Legal 216 × 356
A page is matched to a standard name when both dimensions are
within 2 mm, in either orientation. Anything else is Custom.
Worked example
Example: a merged submission
| A4 portrait — 210 × 297 mm | 18 pages |
| Letter portrait — 216 × 279 mm | 4 pages |
| A4 landscape — 297 × 210 mm | 2 pages |
Printing this on A4 shrinks the four Letter pages slightly and leaves inconsistent margins. Converting everything to A4 first avoids it.
What your result means
One size reported means the document will print consistently.
Several sizes means print output will vary page to page — scaled down, or with content near the edges clipped.
"Custom" usually means a scan or a page produced at a non-standard size. It will be scaled by the printer to fit whatever paper you use.
Important considerations
- A4 and Letter differ by only 6 mm in width and 18 mm in height, which is why the problem goes unnoticed until something is printed.
- Indian printing uses A-series paper almost exclusively. Documents from American sources are frequently Letter-sized.
- Rotation is separate from page size. An A4 page rotated 90° is still recorded as A4 — the rotate tool handles orientation.
- Print shops charge by paper size. A document containing A3 pages costs more, and it is better to know before you arrive.
- Cropping changes the visible area but not the underlying page size in every reader.
Limitations of this tool
- Password-protected PDFs cannot be opened without the password and will report an error rather than failing quietly.
- Everything runs in your device's memory, so very large documents can be slow or exhaust available memory.
- Damaged or partially downloaded files cannot be parsed.
- Only the first 500 pages are measured on very long documents.
- The MediaBox is measured. Where a CropBox differs, readers may display a smaller area than reported.
Frequently asked questions
How do I know if my PDF is A4?
Select it here. A4 is 210 × 297 mm, or 595 × 842 points. The tool names the size for you rather than making you compare numbers.
Why do some pages print smaller than others?
Because the document contains mixed page sizes. The printer scales everything to the paper in the tray, so a Letter page on A4 paper prints slightly smaller with different margins.
What is the difference between A4 and Letter?
A4 is 210 × 297 mm; Letter is 216 × 279 mm. Letter is wider and shorter. India uses A4 almost exclusively; the United States uses Letter.
How do I make every page the same size?
Use the page size converter, which re-renders every page onto a consistent size.