Website Tech Stack Detector - CMS, Analytics, Marketing, Email & DNS

Find out which technologies any list of websites uses: CMS and site builder, e-commerce platform, analytics and tag managers, advertising pixels, marketing automation and CRM, live chat, payments, JavaScript frameworks, CDN, hosting and web server. It also reads public DNS to show email hosting (Google Workspace, Microsoft 365...), email-sending services (SendGrid, Amazon SES, Mailgun...), DNS hosting, DMARC policy and verified SaaS tools (Atlassian, Slack, DocuSign, Zoom...). It's a fast, low-cost BuiltWith / Wappalyzer alternative for lead lists and market research.

What does it do?

For each domain it:

1. Fetches the public homepage once (only if robots.txt allows it) and checks HTTP headers, cookie names, <script>, <link> and <meta> tags and HTML markers.
2. Queries public DNS: MX, TXT/SPF, NS and _dmarc records.
3. Matches everything against 192 technology signatures, adds versions where they are visible (e.g. WordPress, nginx, Angular), and rates each detection high, medium or low confidence with the evidence (detectedVia).

No browser and no proxies: about 1 second per domain, with up to 30 domains in parallel.

Who is it for?

• Sales and lead-gen teams: build "companies using Shopify + Klaviyo" or "sites on HubSpot" lists with the onlySitesUsing filter, then personalize outreach.
• Agencies and SaaS marketers: find prospects on a competitor's platform, or find migration opportunities (e.g. Universal Analytics leftovers, old jQuery versions).
• Investors and analysts: technographic snapshots of a portfolio or market.
• IT and security teams: an inventory of email security (SPF, DMARC, gateways) and CDNs across many domains.

Input

Field	Description
domains	Domains or URLs, one per line
onlySitesUsing	Optional: output only sites using any of these technologies (e.g. Shopify, HubSpot)
analyzeHtml / analyzeDns	Turn either detection layer on or off (both on by default)
includeEvidence	Add detectedVia per technology
includeDnsRecords	Add raw MX / NS / SPF records
maxItems / maxConcurrency	Limits

Output

One record per domain. Real example (shortened):

{
    "domain": "apify.com",
    "finalUrl": "https://apify.com/",
    "statusCode": 200,
    "title": "Apify: Marketplace of ready-to-run tools for AI",
    "technologyCount": 13,
    "technologyNames": "Amazon CloudFront, Amazon Route 53, Google Workspace, DMARC, Next.js, React, Intercom, HubSpot, Google Search Console, HSTS, Google Tag Manager, Amazon SES, Mailgun",
    "cms": [],
    "analytics": ["Google Tag Manager"],
    "marketingAutomation": ["HubSpot"],
    "liveChatAndSupport": ["Intercom"],
    "jsFrameworks": ["Next.js", "React"],
    "cdnAndHosting": ["Amazon CloudFront"],
    "emailHosting": ["Google Workspace"],
    "emailSendingServices": ["Amazon SES", "Mailgun"],
    "dnsHosting": ["Amazon Route 53"],
    "hasSpf": true,
    "dmarcPolicy": "reject",
    "technologies": [
        {"name": "Next.js", "category": "JavaScript framework", "version": null, "detectedVia": ["html"], "confidence": "medium"},
        {"name": "HubSpot", "category": "Marketing automation", "version": null, "detectedVia": ["script", "dns-spf"], "confidence": "high"}
    ]
}

Summary fields: cms, ecommercePlatform, analytics, advertising, marketingAutomation, liveChatAndSupport, payments, jsFrameworks, cdnAndHosting, webServer, emailHosting, emailSendingServices, dnsHosting. The technologyNames column is handy for CSV and Excel.

Pricing

Pay per event, no monthly fee:

• $2.50 per 1,000 websites analyzed ($0.0025 per site).
• $0.005 per run start fee.

You only pay for websites whose results are saved to the dataset. Set a maximum cost per run to cap spending.

Responsible use and data

• One polite request per site. The Actor reads robots.txt first. If the homepage is disallowed, it skips the HTML and reports DNS-only results with a note.
• No bypassing. If a site blocks automated visitors (403, challenge pages), the Actor reports the status code and DNS results and does not retry through proxies or browsers.
• No personal data. The output is about technologies, not people. Cookie values and raw TXT verification tokens are never output.
• The technology signatures were written for this Actor. No third-party fingerprint database is copied.

Limits and notes

• Detection is based on the homepage only. Tools loaded only on inner pages, after cookie consent, or by a tag manager at runtime can be missed. DNS detection helps fill the gap.
• Apex-domain DNS is used (www. is stripped). Subdomain-specific email setups can differ.
• Signatures are maintained and extended over time. Ask for a technology in the Issues tab.

FAQ

How is this different from BuiltWith or Wappalyzer? It's pay-per-result with no subscription, it runs on your own list, and it adds DNS-based detection (email provider, SPF senders, DMARC, verified SaaS) that HTML-only tools miss.

What does "confidence" mean? high: a specific header, meta tag, script URL, cookie or DNS record matched (or several signals agreed). medium: a single HTML marker matched. low: implied by another technology (e.g. WooCommerce implies WordPress).