Convert Dots per pica to Pixels per inch
Convert Dots per pica (dot/pica) to Pixels per inch (PPI) instantly and accurately.
Conversion Formula
PPI = dot/pica × 6
About Dots per pica
The dot per pica (dot/pica) is a typographic resolution unit linking printer DPI to the pica - exactly 1/6 inch in the PostScript standard (Adobe, 1985). A 72 DPI Macintosh screen placed exactly 12 dots per pica (1 dot per point); a 300 DPI LaserWriter placed 300/6 = 50 dot/pica, providing 50-level halftone cells per pica. High-end digital imagesetter platemakers: Agfa Selectset Avantra 45 at 3600 DPI = 600 dot/pica; modern 2400 DPI proofers produce 400 dot/pica. Desktop publishing software - Adobe InDesign, QuarkXPress, Affinity Publisher - defaults to pica+point rulers (e.g., 4p6 = 4 picas 6 points = 0.75 inch), making dot/pica a natural precision unit for typographic rasterisation quality assessment. 1 dot/pica = 6 DPI = 6 PPI (since 1 pica = 1/6 in). 1 dot/pica = 6 PPI = 15.24 dot/m.
About Pixels per inch
The pixel per inch (PPI) is the universal standard for digital image resolution, defining how many pixels occupy one linear inch in a digital image, sensor, or display. Formally referenced in ISO 12232 (digital still cameras) and EXIF/TIFF (tags 0x011A/0x011B), PPI is both a capture parameter (scanner/sensor density) and a display characteristic. Display milestones: Macintosh 128K (1984): 72 PPI; Apple iPhone 4 Retina (2010): 326 PPI - above the human perceptual threshold at 25 cm; iPhone 15 Pro (2023): 460 PPI. Print benchmarks: 150 PPI (large-format, 1 m viewing); 300 PPI (standard offset, ISO 12647-2); 400-600 PPI (fine-art Giclée). EXIF stores PPI as unsigned RATIONAL; the historical default is 72/1, a carry-over from the original Macintosh screen standard. 1 PPI = 1/0.0254 px/m ≈ 39.37 px/m = 2.54 px/cm.
Quick Reference Table
| Dots per pica (dot/pica) | Pixels per inch (PPI) |
|---|---|
| 1 dot/pica | 6 PPI |
| 2 dot/pica | 12 PPI |
| 5 dot/pica | 30 PPI |
| 10 dot/pica | 60 PPI |
| 25 dot/pica | 150 PPI |
| 50 dot/pica | 300 PPI |
| 100 dot/pica | 600 PPI |