Open source tool by Ben Treder

WD-404 Website Diagnostics

WD-404 is a website diagnostics tool that crawls a site and reports on broken pages, redirect chains, crawl issues, and other common problems that slow websites down and hurt search visibility. It gives you a clear picture of what is going wrong before visitors or search engines have to find it themselves.

Most websites pick up broken links and redirect problems over time as pages move, get renamed, or get deleted. WD-404 was built to make it easy to spot those problems without having to click through the site manually or rely on expensive third-party auditing tools.

TypeOpen source Rust CLI
Best forWebsite owners and developers
FocusSEO, security, and link diagnostics

WD-404 runs entirely on your machine. It only contacts the website you point it at, and the local dashboard binds to 127.0.0.1 only.

What WD-404 checks

WD-404 crawls through a website and collects information about page status, redirects, and accessibility issues that are easy to miss when reviewing a site manually.

SEO checks

Titles, meta descriptions, headings, canonical tags, robots.txt, sitemap, Open Graph tags, Twitter cards, and image alt text.

Security checks

HTTPS enforcement, security headers, mixed-content detection, and WordPress endpoint exposure.

Link analysis

Internal and external link counts, broken link detection, and redirect chain tracking.

Weighted scoring

Combines SEO, security, and link results into a single score (SEO 40%, Security 35%, Links 25%) with an A+ to F grade.

Local dashboard

Run wd-404 dashboard and review results in a local, no-CDN web UI at 127.0.0.1:3000.

Client-ready reports

Export Markdown, dark-theme HTML, or JSON reports, or use your browser's Print / Save as PDF from the dashboard.

How it runs

WD-404 is a Rust command-line tool built to stay predictable and contained.

  • Only contacts the site you point it at — no other network calls
  • Read-only requests (GET/HEAD); nothing is posted
  • Private and internal IP ranges are blocked
  • Each request times out after 10 seconds, redirects capped at 5
  • A crawl checks up to 25 pages
  • The dashboard binds to 127.0.0.1 only, never exposed publicly

CLI examples

From the repo's documented usage.

wd-404 --version wd-404 scan https://example.com wd-404 scan https://example.com --save wd-404 report https://example.com --format html wd-404 dashboard

A look at the WD-404 dashboard

Real screenshots from the project's repository, covering the dashboard, scan overview, and the SEO, security, link, and history detail pages.

WD-404 local dashboard home screen
Dashboard home
WD-404 scan overview with score and top priorities
Scan overview
WD-404 SEO detail page
SEO details
WD-404 security detail page
Security details
WD-404 link analysis detail page
Link details
WD-404 exportable report page
Report page
WD-404 scan history page
Scan history

Why I built this

Broken pages and messy redirects show up on almost every website I work on. Most of the time the site owner has no idea because they are focused on running their business, not checking every URL. WD-404 started as something I ran internally to get a fast picture of a site before digging into fixes.

Built for real workflow Open source Practical diagnostics Small business friendly

Related tools

WD-404 is one of a few local, preview-first tools built the same way.

Find your website's problems before visitors do.

WD-404 is open source and free. The full source code, install instructions, and release notes are in the GitHub repository.