Color-Contrast Subscribe to Color-Contrast RSS feed

↻ 2026-09-23 Updated The report’s “+22.5% elements in a single year” isn’t what you get from last year’s 1,257, so I asked WebAIM. They confirmed a calculation error and corrected the report to +14.3% (1,257 → 1,437 elements) in a reply on September 21; this post, first published on July 28, is updated to match. The 22.5% matches the two-year change since 2024 exactly. At 14.3% it is still the largest one-year jump since the study began, so the conclusions stand. What happens when you run one million home pages through an automated accessibility checker? ...

I had clearly written a dark gray into my CSS. color: #595959. On a white background that color has a contrast of 6.4:1, which comfortably clears the accessibility bar of 4.5:1. Pass. Then I ran an accessibility checker, and a red line appeared. This text has a contrast of 4.04:1, which is insufficient. Expected ratio: 4.5:1. I put in a color that measures 6.4:1, so why is it calling it 4:1? Was the checker wrong? ...

I turned on dark mode and my eyes hurt more. The background was black but the text was a heavy gray, so the contrast was far too low; links were still the default blue (#0000ff), which stung. Images blazed alone against the dark screen. One button was the same color as its background, so it was simply invisible. It said “dark mode supported.” But it was dark mode by color inversion, nothing more. ...

Introduction “We used red and green to distinguish them, so it should be fine.” It’s a thought that comes up naturally during development. But more people than you’d expect have difficulty telling those two colors apart. Statistics based on Northern European ancestry suggest that roughly 1 in 12 men and 1 in 200 women have red-green color vision deficiency. The exact ratio varies by region and genetic background, but the fact remains: there are always users who struggle to distinguish red from green. ...