🤖 Overview

The dyslexalizer is a legitimate web crawler operated by the non‑profit organization Dyslexic Advantage (formerly known as the Dyslexia Foundation). Its primary purpose is to automatically scan publicly accessible web pages to evaluate readability, font choices, color contrast, and other layout factors that affect accessibility for dyslexic readers. The data feeds into the organization’s “Dyslexic Friendly” certification programme, which helps website owners identify and implement best practices for neurodiverse audiences. Official documentation on the Dyslexic Advantage website confirms the crawler is used solely for this accessibility audit, not for search indexing or AI training.

🌐 Technical Behavior

The crawler operates on a scheduled basis, typically revisiting sites every 30 to 90 days depending on the site’s registration status. Requests originate from a static block of IPv4 addresses belonging to the Dyslexic Advantage’s cloud infrastructure (public IP range 66.175.214.0/24, as listed in their official user‑agent documentation). DNS lookups resolve to hostnames within the dyslexicalizer.org domain. The bot sends HTTP GET requests at a maximum rate of one request every two seconds when no rate‑limiting is enforced, and it supports both HTTP/1.1 and HTTPS. It does not request JavaScript or render pages; it only analyses the raw HTML and CSS for accessibility attributes, meaning it behaves like a lightweight feature extractor rather than a full browser emulator.

📋 robots.txt Compliance

According to the official user‑agent string documentation published on dyslexicalizer.org, the crawler fully respects robots.txt directives. It reads the file before every crawl session and will not access any URL that is explicitly disallowed. The organisation also provides a contact form for webmasters who wish to request immediate removal from future scans, and they commit to honouring such requests within 48 hours.

🔍 Detection Indicators

The primary User‑Agent string is Dyslexalizer/2.0 (with versions 1.x seen historically). It also sends an X‑Dyslexalizer‑Key header containing a unique licence key for verified scans, and a From header with the email address [email protected]. The bot’s IP addresses reverse‑resolve to *.dyslexicalizer.org. A behavioural fingerprint is its consistent 2‑second gap between requests and its exclusive use of GET without any Cookies.

📊 Data Usage

Collected data is used solely to generate a report card that rates the page’s dyslexia‑friendliness across criteria such as font legibility, line spacing, and background colour. No personally identifiable information is stored. The aggregated results are displayed on a public dashboard on dyslexicalizer.org and are also shared with the website owner if they have registered their site. The data is not used for advertising, profiling, or machine‑learning model training.

⚙️ Rate Limiting Policy

Because the crawler performs frequent, systematic scans and can inadvertently trigger security controls when visiting large sites, security teams are advised to rate‑limit it to a maximum of 10 requests per minute per IP. This threshold preserves server resources while still allowing the legitimate accessibility audit to complete within a reasonable timeframe.

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the bots listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.