Optimal Font Size and Line Height for Digital Reading (2026)
· Alex
The three numbers that make digital text readable: 16 px minimum body size, 1.4-1.6 line height, 45-75 characters per line — with WCAG, Nielsen Norman, and Bringhurst citations.
Three numbers decide whether a paragraph is easy or painful to read: font size, line height, and line length. Get them right and your text becomes invisible — the reader absorbs meaning without noticing the mechanics. Get them wrong and even a brilliant sentence feels heavy.
Font Size: 16 px Is the Floor, Not the Ceiling
Line Height: Aim for 1.4 to 1.6
Line Length: 45 to 75 Characters Per Line
How Agentys Applies the Three Rules
Readable typography is not magic — it is three numbers applied with discipline: 16 px or more, line-height 1.4 to 1.6, 45 to 75 characters per line. Agentys enforces those numbers so your readers stay focused on your message rather than fighting your layout.