Screen pixels lie about print quality
A logo that looks sharp on a Retina display may print soft at business-card size. DPI is pixels divided by physical inches — when that ratio drops below 200, edges fuzz on paper.
300 DPI is the safe default for photos and fine brand marks viewed up close. Large posters viewed from a distance can tolerate lower DPI — but know the viewing distance before you export.
Work backward from print size when briefing designers: 4×6 at 300 DPI needs 1200×1800px minimum. Brand Studio helps you keep those specs consistent across collateral.