Open Settings > Accessibility > Display & Text Size. Turn on Bold Text. Text across the system is displayed with increased weight for improved readability.
Note: After enabling this option, iOS prompts to briefly reload the interface.
Bold Text
Applies a heavier system font weight on iOS to improve readability.
What does this setting do?
“Bold Text” increases the visual weight of all system fonts, making characters easier to distinguish. This is especially helpful when thin fonts are difficult to read or when low contrast affects legibility. The feature exists only on iOS. Other operating systems do not provide a system-wide bold text option.
Instructions for different systems
Für dieses Betriebssystem ist keine Anleitung verfügbar.
Für dieses Betriebssystem ist keine Anleitung verfügbar.
Für dieses Betriebssystem ist keine Anleitung verfügbar.
Often mentioned in relation to the following conditions:
- Presbyopia – Age-related difficulty focusing on small or close text.
- Age-related Vision Changes – Reduced sharpness, color distinction and tolerance for small text.
- Low Contrast Sensitivity – Reduced ability to distinguish text or icons when contrast is low.
- Color Vision Weakness – Difficulty distinguishing certain colors, often red–green or blue–yellow.
- Age-related Cognitive Changes – Slower processing, reduced working memory, and difficulty with complex navigation.
- Chronic Fatigue – Persistent physical and mental exhaustion with limited energy availability. Attention, processing speed, and resilience are often reduced over extended periods.
Commonly used for the following difficulties:
Low Contrast Tolerance
Low contrast text or icons can be difficult to recognize. High-contrast modes or bold text improve visibility.
Difficulty Reading Small or Dense Text
Small or tightly packed text can cause strain or slow reading. Larger text, increased spacing and reader modes help improve clarity.
Screen Glare Sensitivity
Users with glare sensitivity struggle with reflections or bright hotspots on screens. Lowering brightness, increasing contrast, or using dark mode can reduce strain.
Other settings frequently used together
Relation to WCAG guidelines
For setting to be effective, a website or app often must be technically implemented in such a way that it respects operating system and browser settings.
Developers and designers should follow the Web Content Accessibility Guidelines (WCAG). The following WCAG criteria are particularly relevant for this setting:
1.4.31.4.6