ガイド
Webサイトの低コントラスト文字を修正する方法
読みにくいテキストを見つけて修正する実践的な手順を解説します。
『文字が読みづらい』という指摘は、全面改修なしでも改善できることがほとんどです。失敗箇所を特定し、安全に色を調整する流れを紹介します。
Audit the worst readability problems first
Start with body text, form labels, buttons, and links on high-traffic pages.
Collect failing pairs in a short list so your fixes stay focused.
- Homepage hero text
- Primary/secondary buttons
- Form helper and error text
Measure each text/background pair
Run each pair in a contrast checker and note failed AA/AAA targets.
Keep one table with current value, target, and proposed fix.
Adjust color without breaking brand style
Change lightness first before changing hue.
Small shifts can improve readability while keeping your visual identity recognizable.
Retest UI states and responsive layouts
Check hover, focus, disabled, and visited states.
Confirm results on mobile where smaller text magnifies contrast problems.
Ship and document new color tokens
After fixes pass, update your design system tokens and component docs.
This prevents the same low-contrast values from returning later.
When this guide helps
- Fixing readability complaints from users.
- Improving old pages before relaunch.
- Cleaning up inconsistent legacy color styles.
Fix contrast in controlled iterations
Work through the highest-impact text first, test each change, and lock improved values into your design tokens.