jarmin.com Accessibility Guide - Resources

Validation & Testing

W3C HTML Validation Service
W3C CSS Validator Service
WDG HTML Validator
WDG CSSCheck
W3C Log Validator - uses the web server logs to check the most popular pages of a website for validity with regards to web standards.
HTML Tidy - online version of the tool created by Dave Raggett at the W3C. (About HTML Tidy.)
WaiZilla - open source project aimed at producing a cross platform website accessibility testing tool.
Common XHTML Validation Errors explained.

Accessibility Testing Software Compared (July 2003).
Cynthia Says
Bobby - Checks for Priority 1, 2 and 3 Accessibility, Browser Compatibility Errors and Download Time. Bobby is the best known and most abused accessibility checker. Like all such tools it is a tool for developers to identify possible accessibility problems. One needs some background knowledge to interpret Bobby's comments.
WAVE Accessibility Checker 2.01
WAVE Web Accessibility Validator (3.0 alpha)
Accessibility Toolkit - the accessibility testing meta page.
A-Prompt Toolkit - downloadable software that evaluates web pages for accessibility problems.
W3C WAI: Evaluation, Repair, and Transformation Tools for Web Content Accessibility.
WebAIM: Screen Reader Simulation
Free Accessibility Assessment by SSB Technologies.

Colorblind Web Page Filter - excellent tool that "shows your existing web site through color blind eyes".
Vicheck Color Vision Simulator - simulates how a page looks to someone with a colour deficit.
[de] Sehbehinderungs-Simulator - demonstrates the effect of a variety of medical eye conditions on a number of pictures. Not for evaluating your website. In german.