Paper Size Chart (Free) — A/B Series, mm & px Converter
Free reference chart of standard paper sizes — ISO A series, JIS B series, business cards, postcards, and US Letter/Legal — with exact mm and px dimensions (at 96dpi and 300dpi). Includes a live mm-to-px converter.
Paper Size Reference Table (mm & px)
| Category | Name | Size (mm) | px (96dpi) | px (300dpi) |
|---|---|---|---|---|
| ISO A series | A0 | 841 × 1189 mm | 3179 × 4494 px | 9933 × 14043 px |
| ISO A series | A1 | 594 × 841 mm | 2245 × 3179 px | 7016 × 9933 px |
| ISO A series | A2 | 420 × 594 mm | 1587 × 2245 px | 4961 × 7016 px |
| ISO A series | A3 | 297 × 420 mm | 1123 × 1587 px | 3508 × 4961 px |
| ISO A series | A4 | 210 × 297 mm | 794 × 1123 px | 2480 × 3508 px |
| ISO A series | A5 | 148 × 210 mm | 559 × 794 px | 1748 × 2480 px |
| ISO A series | A6 | 105 × 148 mm | 397 × 559 px | 1240 × 1748 px |
| ISO A series | A7 | 74 × 105 mm | 280 × 397 px | 874 × 1240 px |
| ISO A series | A8 | 52 × 74 mm | 197 × 280 px | 614 × 874 px |
| ISO A series | A9 | 37 × 52 mm | 140 × 197 px | 437 × 614 px |
| ISO A series | A10 | 26 × 37 mm | 98 × 140 px | 307 × 437 px |
| JIS B series | B0 | 1030 × 1456 mm | 3893 × 5503 px | 12165 × 17197 px |
| JIS B series | B1 | 728 × 1030 mm | 2751 × 3893 px | 8598 × 12165 px |
| JIS B series | B2 | 515 × 728 mm | 1946 × 2751 px | 6083 × 8598 px |
| JIS B series | B3 | 364 × 515 mm | 1376 × 1946 px | 4299 × 6083 px |
| JIS B series | B4 | 257 × 364 mm | 971 × 1376 px | 3035 × 4299 px |
| JIS B series | B5 | 182 × 257 mm | 688 × 971 px | 2150 × 3035 px |
| JIS B series | B6 | 128 × 182 mm | 484 × 688 px | 1512 × 2150 px |
| JIS B series | B7 | 91 × 128 mm | 344 × 484 px | 1075 × 1512 px |
| JIS B series | B8 | 64 × 91 mm | 242 × 344 px | 756 × 1075 px |
| JIS B series | B9 | 45 × 64 mm | 170 × 242 px | 531 × 756 px |
| JIS B series | B10 | 32 × 45 mm | 121 × 170 px | 378 × 531 px |
| Business & postal formats | Business card | 91 × 55 mm | 344 × 208 px | 1075 × 650 px |
| Business & postal formats | Postcard | 100 × 148 mm | 378 × 559 px | 1181 × 1748 px |
| Business & postal formats | US Letter | 215.9 × 279.4 mm | 816 × 1056 px | 2550 × 3300 px |
| Business & postal formats | US Legal | 215.9 × 355.6 mm | 816 × 1344 px | 2550 × 4200 px |
Pixel values are calculated as mm ÷ 25.4 × dpi, rounded to the nearest whole number. 96dpi is the standard reference resolution for web/CSS, and 300dpi is the standard for commercial printing.
What Is the Paper Size Chart?
This tool is a quick-reference chart for the paper sizes people run into most often — the ISO A series, the JIS B series, business cards, postcards, and US Letter/Legal — showing each one in both millimeters (mm) and pixels (px) at a glance. It saves you the trouble of looking up "how many millimeters is this sheet?" or "how many pixels should I design at?" during web design or print production work.
Beyond the reference table, the page also includes a live mm-to-px converter: pick any resolution (dpi) and convert a custom size on the spot. You can also see, in one place, the pitfalls that a simple unit conversion alone would not reveal — such as the difference between the ISO and JIS standards, or the gap between Japanese and international conventions for everyday formats.
How to Use the Paper Size Chart
- Find the sheet you need in the table Use the "Category" and "Name" columns to locate the size you want among the ISO A series, JIS B series, and business/postal formats.
- Check the mm and px values Compare the mm, 96dpi, and 300dpi columns for that row, and read off the figure that matches your purpose — on-screen display or print.
- Use the converter for a custom size If the size you need is not in the table, enter a value and a dpi into the mm-to-px converter further down the page.
- Switch the dpi to match your use case Recalculate by switching the dpi — 96dpi for screen use, 300dpi for print — depending on what you are producing.
Tips for getting more out of it
- For web design, use the 96dpi pixel values; for print production, use the 300dpi values to get a layout close to actual print size.
- Japan's JIS B series and the ISO 216 B series differ slightly in size, so always confirm which standard a print shop abroad is using.
- Business card and postcard sizes here follow Japanese convention; other countries often use different standard sizes (e.g. Western business cards are typically 88.9×50.8mm).
- In the ISO A series, folding a sheet in half along its short edge always produces the next size down (A4 folded in half becomes A5, and so on).
- US Letter is slightly wider and shorter than A4, so a PDF designed for A4 can print with shifted margins on US Letter paper.
When to Use the Paper Size Chart
Building print stylesheets for a website
Useful for converting between px and mm when setting margins and layout for A4 pages inside an @media print rule.
Submitting print files for business cards or flyers
Check the pixel size at the dpi your print shop requires (usually 300dpi) beforehand, so your submitted files are not the wrong size.
Adjusting print sizes for overseas documents
Gives you a reference point when converting a document from Japan's A4 format into the US Letter size expected by an overseas client.
Preparing materials at school or work
The at-a-glance table makes it easy to compare several paper formats side by side while planning a document's layout.
Paper Size Glossary
- ISO 216
- The international paper size standard set by the International Organization for Standardization. It covers the A series and the international B series, with an aspect ratio fixed at 1:√2 throughout.
- JIS
- The Japanese Industrial Standards. The B series used within Japan (JIS B) differs in size from the ISO B series and is a distinct standard rooted in the Mino-gami paper of the Edo period.
- dpi
- Short for dots per inch — a resolution unit describing the number of dots (pixels) packed into one inch. A higher number means finer, more detailed print or display output.
- US Letter
- The paper size used as the everyday standard in North America (215.9×279.4mm). It is somewhat wider and shorter than Japan's A4 (210×297mm).
- Point (pt)
- A unit of length used in printing and desktop publishing, where 1pt equals 1/72 of an inch. It is commonly used to specify font size (not supported by this tool).
Frequently Asked Questions
Side Note — the paper size born from the square root of two
The defining feature shared by every size in the ISO 216 A series is a fixed aspect ratio of 1:√2 (about 1:1.414). Fold a sheet in half along its short edge, and the resulting sheet is exactly half the area but keeps the same 1:√2 ratio — A0 folded becomes A1, A1 becomes A2, and so on. This elegant property means enlarging or reducing between sizes never wastes paper.
The √2 ratio is often credited to the German physicist and satirist Georg Christoph Lichtenberg, who described its area-preserving, self-similar property in a 1786 letter. The idea was later formalized as the German industrial standard DIN 476 in 1922, which went on to form the basis of the international standard ISO 216, adopted in 1975.
Japan's B series, by contrast, traces back to the Mino-gami paper size used for official documents in the Edo period, and developed independently of the ISO standard. That history is exactly why the JIS B series and the ISO B series differ slightly today — two standards with entirely different cultural origins that happen to share the same name.