Format profile / ARCH-B
Arch B
304.8 × 457.2 mm · 12 × 18 in
Width
304.8 mm
Height
457.2 mm
Area
1,394 cm²
Finished-size ledger
Pixel canvas by resolution
rounded to whole pixelsBleed and safe-area canvases
confirm with your printer3 mm on every edge
310.8 × 463.2 mm
Artwork canvas with bleed. Keep essential content inside roughly 298.8 × 451.2 mm if the same distance is also used as a simple safety margin.
5 mm on every edge
314.8 × 467.2 mm
Artwork canvas with bleed. Keep essential content inside roughly 294.8 × 447.2 mm if the same distance is also used as a simple safety margin.
Closest standard formats
both edges comparedWhere Arch B fits
2 common usesNext in the North America drawer
larger / smallerSet up Arch B artwork without guessing
Start the document at the finished size—304.8 × 457.2 mm—and add the bleed your printer specifies outside that edge. A common 3 mm bleed produces a 310.8 × 463.2 mm artwork canvas. Keep type, logos, folds, and other critical details inside the trim line; a safety margin is not the same thing as bleed.
Pixel dimensions only become meaningful when paired with a resolution. At 300 DPI, this format is 3,600 × 5,400 pixels. Changing that number in an export dialog without resampling does not add image detail—it only changes the declared physical scale.
Arch B belongs to the North American group. Its 1:1.5 proportion differs from the ISO √2 family, so moving an existing layout to A-series paper can change margins, line length, and page count.