This paper size reference lists all standard paper dimensions: ISO A-series (A0–A10), B-series, US standard (Letter, Legal, Tabloid), and ANSI engineering sizes. All measurements shown in both millimeters and inches. Switch between series using the tabs below.
How to Use the Paper Size Reference
Use the tabs above to switch between paper size series. All sizes are shown in millimeters and inches for easy reference. Click any tab to load that series instantly.
Which Size to Use When
A4 is the standard for business and personal documents in every country except the US and Canada. US Letter (8.5"×11") is the US and Canada standard. A3 equals US Tabloid (11"×17") approximately — A3 is slightly narrower. A0 is used for large format printing and posters. Legal (8.5"×14") is used for legal documents, wills, and contracts in the US.
ANSI Engineering Sizes
ANSI sizes (A through E) are used in engineering drawings and CAD output. ANSI A = US Letter (8.5"×11"). ANSI B = Tabloid (11"×17"). ANSI C = 17"×22". ANSI D = 22"×34". ANSI E = 34"×44".
B-Series Usage
The ISO B-series fills gaps between A-sizes. B5 is between A4 and A5, used for books and notebooks. B4 is between A3 and A4, used for newspapers. B-series is less common than A-series in everyday use.
Frequently Asked Questions
Is this paper size reference free?
Yes, completely free with no signup required.
Is my data safe when using this tool?
Yes. This reference runs entirely in your browser. No data is sent to any server.
What size is A4 paper in inches?
A4 is 210 x 297mm, which equals 8.27 x 11.69 inches. It is the most commonly used paper size internationally. In the US, Letter (8.5 x 11 inches = 216 x 279mm) is the standard for most documents.
What is the difference between US Letter and A4?
US Letter is 8.5 x 11 inches (216 x 279mm) — slightly wider and slightly shorter than A4 (210 x 297mm). If you print an A4 document on US Letter paper, it may get cut off at the bottom. When sharing documents internationally, use PDF which preserves exact page dimensions.
What is the A series paper size system?
The ISO A-series uses a consistent 1:√2 (approximately 1:1.414) aspect ratio. This means folding any A-size sheet in half gives you the next smaller size: folding A4 gives A5, folding A3 gives A4, etc. A0 is the base size at 1 square meter area.
What is Tabloid paper size?
Tabloid (also called Ledger) is 11 x 17 inches (279 x 432mm). It is the standard US size for newspapers, large-format documents, and architectural sketches. When printed landscape, it is called Ledger; when printed portrait, it is called Tabloid.