Paper Formats

Standardized international metric paper sizes defined by ISO 216 (DIN 476), based on the unique mathematical root-two aspect ratio (1:1.4142) where folding or cutting a sheet in half produces the next smaller size with identical proportions.

A0 • A1 • A10 • A2 • A3 • A4 • A5 • A6 • A7 • A8 • A9

Standardized international paper sizes defined by ISO 216 whose dimensions are the geometric mean of adjacent A-series sheets (Bn = √(An × An-1)), designed for book publishing, posters, passports, and applications where A-series leaves too large a sizing gap.

B0 • B1 • B2 • B3 • B4 • B5 • B6 • B7

Historical and commercial bookbinding formats defined by folding a full printer's sheet into signatures (Folio, Quarto, Octavo, Duodecimo), along with modern commercial publishing mass-market and trade paperback standards.

Duodecimo • Folio • Mass Market Paperback • Octavo • Quarto • Trade Paperback

Standardized international postal envelope sizes defined by ISO 269 (DIN 678), where each Cn envelope's dimensions are the geometric mean of An and Bn (Cn = √(An × Bn)), engineered so that an An paper sheet slides cleanly inside an unfolded Cn envelope.

C3 Envelope • C4 Envelope • C5 Envelope • C6 Envelope • C7/C6 Envelope • DL Envelope

Standardized imperial inch-based paper dimensions dominant across the United States, Canada, and Mexico, standardized under ANSI/ASME Y14.1 (Engineering Drawing Sheet Size) and Architectural (Arch) series specifications.

ANSI C • ANSI D • ANSI E • Arch D • US Executive • US Half Letter • US Legal • US Letter • US Tabloid / Ledger

Standardized metrics for paper density, basis weight, and sheet thickness defined by ISO 536 (Metric Grams per Square Meter / GSM), North American TAPPI Basis Weight grades (Bond, Text, Cover), and micrometer point calipers.

Bond / Ledger Weight • Cover / Cardstock Weight • GSM Grammage • Paper Caliper • Text / Book Weight