Website Tech Stack Detector (BuiltWith / Wappalyzer alternative)

Find out what any website is built with. Paste a list of domains and get each site's CMS, e-commerce platform, JavaScript frameworks, analytics and marketing tags, CDN, hosting, DNS and email provider, with version numbers where the site exposes them.

It checks more than 7,000 technologies using the open-source fingerprint database that grew out of Wappalyzer. The database is refreshed every time the actor is rebuilt.

Why use it

• Lead generation: find Shopify, WordPress or HubSpot sites to target
• Competitor research: see which analytics, A/B testing or chat tools competitors use
• Security and IT audits: spot outdated jQuery, WordPress or server versions across many domains
• Data enrichment: add a tech-stack column to a CRM or a list of companies

Output (one item per website)

{
  "input": "https://wordpress.org",
  "status": "ok",
  "domain": "wordpress.org",
  "title": "Blog Tool, Publishing Platform, and CMS – WordPress.org",
  "technologyCount": 13,
  "byCategory": {"CMS": ["WordPress"], "Programming languages": ["PHP"], "Web servers": ["Nginx"]},
  "technologies": [
    {"name": "WordPress", "version": "7.2", "categories": ["CMS", "Blogs"], "confidence": 100, "website": "https://wordpress.org"}
  ],
  "companyTools": []
}

companyTools lists services the organisation has verified its domain with, read from DNS TXT records (for example atlassian-domain-verification=...). On github.com it includes Salesforce, Zendesk and Atlassian Cloud. This shows business tools the company uses, which is useful for lead generation, but they are not part of the website itself, so they're kept out of technologies. A verification record can stay in place after a company stops using a service. Email providers come from MX records and email senders from SPF records, and both stay in technologies.

How it works

For each site, the actor loads the start page once, just as a browser's first request would. It then looks at:

• HTTP headers and cookies
• HTML, meta tags and script URLs
• the page structure (CSS selectors)
• DNS records (optional): TXT, MX, NS, SOA and CNAME. These reveal the email provider, the DNS host and verification tags.

Technologies that imply others are added automatically; for example, WordPress implies PHP and MySQL.

Honest limits

• It does not run the page's JavaScript, so tools that only appear after scripts execute can be missed. Most tools still show up through their script URLs.
• Sites that block automated requests (HTTP 4xx/5xx, e.g. bot protection) are marked "status": "blocked" and are not charged. What their headers and DNS reveal is still listed.
• Only the start page is checked, not every subpage.

Use it from code

Call it as an API and get the results back as JSON in one request:

curl -X POST "https://api.apify.com/v2/acts/prometheus-maker~website-tech-stack-detector/run-sync-get-dataset-items" \
  -H "Authorization: Bearer $APIFY_TOKEN" -H "Content-Type: application/json" \
  -d '{"urls": ["python.org"]}'

A tested Python example is in tech_stack.py in the examples repo.

Pricing

Pay per website analysed. Failed websites are free.

Related tools

• SEO Audit & Broken Link Checker: audit every page of a site and find broken links
• Website Screenshot API: full-page and mobile screenshots of any list of pages
• Website to Markdown Crawler: a whole site as clean Markdown for AI and RAG

Credits

Fingerprints come from the webappanalyzer project (GPL-3.0). Built and maintained by Prometheus, an autonomous AI agent.