Saved in:
Bibliographic Details
Main Authors: Vaughan, Thom, Suarez, Pedro Ortiz
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2602.24067
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908855900831744
author Vaughan, Thom
Suarez, Pedro Ortiz
author_facet Vaughan, Thom
Suarez, Pedro Ortiz
contents We present a large-scale automated audit of WCAG 2.1/2.2 Level AA colour contrast compliance across the 500 most frequently crawled registered domains in Common Crawl's CC-MAIN-2026-08 February 2026 crawl archive. Rather than conducting a live crawl, all page content was sourced from Common Crawl's open WARC archives, ensuring reproducibility and eliminating any load on target web servers. Our static CSS analysis of 240 homepages identified 4,327 unique foreground/background colour pairings, of which 1,771 (40.9%) failed to meet the 4.5:1 contrast ratio threshold for normal text. The median per-site pass rate was 62.7%, with 20.4% of sites achieving full compliance across all detected colour pairings. These findings suggest that colour contrast remains a widespread accessibility barrier on the most prominent websites, with significant variation across domain categories.
format Preprint
id arxiv_https___arxiv_org_abs_2602_24067
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Colour Contrast on the Web: A WCAG 2.1 Level AA Compliance Audit of Common Crawl's Top 500 Domains
Vaughan, Thom
Suarez, Pedro Ortiz
Information Retrieval
Human-Computer Interaction
We present a large-scale automated audit of WCAG 2.1/2.2 Level AA colour contrast compliance across the 500 most frequently crawled registered domains in Common Crawl's CC-MAIN-2026-08 February 2026 crawl archive. Rather than conducting a live crawl, all page content was sourced from Common Crawl's open WARC archives, ensuring reproducibility and eliminating any load on target web servers. Our static CSS analysis of 240 homepages identified 4,327 unique foreground/background colour pairings, of which 1,771 (40.9%) failed to meet the 4.5:1 contrast ratio threshold for normal text. The median per-site pass rate was 62.7%, with 20.4% of sites achieving full compliance across all detected colour pairings. These findings suggest that colour contrast remains a widespread accessibility barrier on the most prominent websites, with significant variation across domain categories.
title Colour Contrast on the Web: A WCAG 2.1 Level AA Compliance Audit of Common Crawl's Top 500 Domains
topic Information Retrieval
Human-Computer Interaction
url https://arxiv.org/abs/2602.24067