What are the principles of responsive typography?

Responsive typography ensures that text on a website is readable, legible, and visually balanced across all screen sizes—from desktops to smartphones. One of the key principles is using relative units like em, rem, or percentages instead of fixed units like px, allowing font sizes to scale naturally based on the screen or root element.

Another principle is establishing a flexible type scale—a system where heading and body text sizes adjust proportionally depending on the viewport. Line length (typically 50–75 characters per line) and line height (leading) should also adapt to different screen sizes to maintain optimal readability. Choosing web-safe, legible fonts and ensuring sufficient contrast between text and background are also essential for accessibility.

Lastly, responsive typography involves using media queries or fluid typography techniques (like clamp()) to fine-tune how text behaves at different breakpoints. When done right, it enhances the reading experience, keeps users engaged, and makes your website look polished and professional on any device.