If your users scale the text size in Android or iDeviceOS, that doesn’t always affect the size of text on a web page. It’s a function of browser and authored code, as opposed to a standardized approach. That may be changing. Support The current state of affairs in the three…

Adrian Roselli is a web developer, accessibility advocate, and expert in web standards. Readers can learn about web accessibility, inclusive design, and best practices for building accessible websites and applications. With articles, tutorials, and presentations, Adrian Roselli shares  insights and techniques for creating digital experiences that are usable and accessible to everyone.

Adrian Roselli

Mobile browsers handle OS-level text size settings differently. Firefox automatically scales web text with Android system settings. Safari requires specific CSS using `-apple-system-body` font properties. Chrome is introducing a new `<meta name="text-scale" content="scale">` tag that requires authors to avoid fixed font sizes and use relative units. A combined approach using both the meta tag and Safari's CSS can enable text scaling across all three rendering engines, improving accessibility for users who adjust system font sizes.

Honoring Mobile OS Text Size