International Paper Sizes
Look up A4, A3, A5 and every ISO 216 A/B paper size plus ISO 269 C envelopes in millimeters and inches.
Data last maintained
International Paper Sizes
Look up A4, A3, A5 and every ISO 216 A/B paper size plus ISO 269 C envelopes in millimeters and inches.
Data last maintained
About International Paper Sizes
A, B, and C series dimensions
The table lists ISO 216 A and B trimmed paper sizes plus the ISO 269 C envelope series, with dimensions in millimeters and inches. It is meant for quick checks when preparing print layouts, stationery specs, or international document references.
Search or filter by series
Search by size name such as A4 or C5, or use the series filter to focus on A paper, B paper, or C envelopes. The table keeps the size name beside metric and inch values so layout notes can be copied or compared without recalculating.
Not printer setup or postal rules
These dimensions are reference sizes only. They do not include bleed, trim tolerance, printer margins, paper weight, envelope window placement, postage eligibility, or vendor-specific templates. Confirm production requirements with your print shop, mail carrier, or office device settings.
FAQ
Common questions and answers about this topic.
What is A4 size in mm and inches?
A4 measures 210 × 297 mm, which is about 8.27 × 11.69 inches. It is the most common ISO 216 document size and is exactly half the area of A3.
What is A4 size in pixels?
It depends on resolution. At 72 DPI A4 is 595 × 842 px, at 150 DPI it is 1240 × 1754 px, and at 300 DPI (print quality) it is 2480 × 3508 px.
What is the difference between A4 and US Letter?
A4 is 210 × 297 mm (8.27 × 11.69 in); US Letter is 216 × 279 mm (8.5 × 11 in). A4 is narrower and taller, so a document set for one size may not line up when printed on the other.
What are A3 and A5 sizes?
A3 is 297 × 420 mm (11.69 × 16.54 in) — twice the area of A4. A5 is 148 × 210 mm (5.83 × 8.27 in) — half of A4. Each step up doubles the sheet and each step down halves it.
How does the ISO A series sizing work?
Every ISO 216 size keeps the same 1:√2 (about 1:1.414) aspect ratio. Cutting a sheet in half across the long side gives the next smaller size, so A4 folds to A5, A3 to A4, and so on without changing the proportions.
What paper sizes does this chart cover?
It covers the full ISO 216 A series (A0-A10) and B series (B0-B10) trimmed paper sizes, plus the ISO 269 C envelope series (C0-C8), each with millimeter and inch dimensions.
Data Sources
This tool's data is compiled from the authoritative sources below.
- ISO 216:2007 - Writing paper and certain classes of printed matter(opens in a new tab)
- ISO 269:1985 - Correspondence envelopes(opens in a new tab)
- NIST SI Units - Length(opens in a new tab)
Data last maintained