Dynamic Type Support

On-screen text should be sized in scale-independent pixels (sp) so it responds to the user's system font-size setting.

WCAG Reference

Maps to: WCAG 1.4.4 Resize Text | Applies to: WCAG 2.0, WCAG 2.1, WCAG 2.2 Introduced in: WCAG 2.0 | Level: AA | Read the official specification →

What this rule checks

The scanner examines whether on-screen text is sized in sp (scale-independent pixels) — the only Android text unit that responds to the user's system-wide font-size preference. Text sized in fixed units (dp, px, pt, in, mm) renders at a fixed size no matter what the user configures.

note

The required device data is available on Android 11+ only; on older devices the rule passes silently rather than flagging an issue.

Why it matters

Users with low vision commonly increase Android's font-size setting (up to 200%). Text sized in dp or px ignores that setting entirely — it stays small regardless, leaving the user no way to read it short of using a screen magnifier for every interaction. WCAG 1.4.4 requires that text be resizable up to 200% without loss of content or functionality.

Common failure patterns

• android:textSize declared in dp or px to "protect" a layout from large fonts
• custom text rendering that computes pixel sizes directly

Remediation guidance

• replace fixed-unit text sizes with scale-independent units so the accessibility font-scale takes effect — use sp for android:textSize instead of dp or px, and avoid setting a fixed text size on TextView / Button / EditText
• test at the system's largest font-size setting and confirm no text clips or truncates (see Non-Responsive Container Clips Text for the layout side of this)

Related docs

• Non-Responsive Container Clips Text
• Android Rule Repository
• Accessibility Issue Remediation Guide