Body text follows headlines and carries the primary substance of the product. Because users spend 80% of their reading time consuming body copy, ergonomics is paramount:
Key Body Text Rules
Font Size: Standard web body copy must never fall below 16px (1rem). On mobile screens, 14px is an acceptable absolute minimum for subordinate captions.
Line Length (Measure): The optimal line length for reading comfort is 45 to 75 characters per line (including spaces). Lines that are too long cause the eye to lose track of the next line; lines that are too short break reading rhythm.
Font Versatility: Choose typefaces with at least 4 weights (Regular, Medium, Semi-Bold, Bold) to allow nuanced emphasis without switching fonts.
Topics
Typographic Hierarchy & Visual Scanning Pathways
Headlines and Eyebrow Headlines Architecture
Body Text Ergonomics and Accessibility Standards
Text Alignment: Flush Left, Centered, Flush Right, and Justified