When you need this conversion
Print specs from US publishers often mix units: a trim size in inches and a type area in picas. Converting picas to inches shows how much margin is left around the text block, or whether a grid fits a given page.
Worked example: a book page
A 6 × 9 inch book is 36 × 54 picas. With a 26-pica text column (26 ÷ 6 = 4.333 in), you have 6 − 4.333 = 1.667 in left for the inner and outer margins together.
Useful values
- 1 pc = 0.1667 in
- 12 pc = 2 in
- 24 pc = 4 in
- 36 pc = 6 in
- 51 pc = 8.5 in (US Letter width)
Common mistakes
Treating the pica as metric. It’s defined from the inch, so metric conversions carry decimals: 1 pica is 4.2333 mm.
Confusing picas with the font size “pica”. On typewriters, “pica” also named a 10-characters-per-inch typeface. That’s a different thing entirely.
To work in points instead, use picas to points.