Tech Stack Detector - Wappalyzer Alternative + DNS SaaS Stack

What does Tech Stack Detector do?

Tech Stack Detector tells you which technologies any website uses: CMS, ecommerce platform, analytics, marketing automation, CRM, payments, CDN, hosting, frameworks and more. It checks 7,600+ technology fingerprints (the open-source Wappalyzer dataset).

It also reads the website's DNS records, where companies leave traces of the SaaS tools they pay for: email provider (Google Workspace, Microsoft 365), email senders (Mailchimp, SendGrid, Amazon SES, Postmark), CRM and marketing tools (Salesforce, HubSpot, Marketo, Klaviyo), and workplace tools (Atlassian, Zoom, Slack, Notion, OpenAI, Anthropic, and many more). None of these appear in the page HTML, so homepage-only detectors can't see them.

In a test on 25 well-known websites, it found 25 technologies per site on average, and 16 of them came only from DNS.

Why use it?

• 🎯 Lead qualification: find every prospect that runs Shopify, uses HubSpot, or is still on Microsoft Exchange.
• 🕵️ Competitor research: see what your competitors build with and which SaaS they pay for.
• 📧 Sales targeting: know the email provider and marketing stack before you reach out.
• 🏗️ Agency prospecting: find WordPress or Wix sites ready for a redesign or migration.
• 🔌 Enrichment pipelines: clean JSON and flat CSV columns, callable via API, schedules, or integrations (Make, Zapier, n8n, Google Sheets).

How much does it cost?

You pay per website analyzed. Websites that fail are free: domains that don't exist, don't respond or time out are never charged. The run also stops cleanly at your maximum cost per run, so you never get billed for results you didn't get. The only other charge is Apify's standard start fee of $0.00005 per run.

The detector runs without a browser, so it is fast (25 websites in about 10 seconds) and cheap on platform usage.

How to use it

1. Add domains or URLs to Websites (example.com, www.example.com or https://example.com/page).
2. Keep Detect email & SaaS stack from DNS on (recommended).
3. Click Start and download the results as JSON, CSV, Excel or HTML.

Input example

{
    "websites": ["vercel.com", "allbirds.com", "techcrunch.com"],
    "includeDns": true
}

Output

One row per website. The Overview table gives one column per category (easy to filter in a spreadsheet), and technologies has every detection with version, confidence, categories and how it was detected.

Real result for vercel.com (technologies list shortened):

{
    "input": "vercel.com",
    "status": "ok",
    "domain": "vercel.com",
    "finalUrl": "https://vercel.com/",
    "httpStatus": 200,
    "technologyCount": 31,
    "analytics": "Linkedin Insight Tag, Mixpanel, Ahrefs",
    "marketingAutomation": "Marketo",
    "crm": "Salesforce",
    "emailHosting": "Google Workspace, Microsoft 365",
    "emailSending": "Amazon SES, Postmark, Sendgrid",
    "payments": "Stripe",
    "hosting": "Amazon Web Services, Vercel",
    "frameworks": "Next.js, React",
    "ai": "Anthropic, Cursor, OpenAI",
    "technologies": [
        { "name": "Salesforce", "version": "", "confidence": 100, "categories": ["CRM"], "website": "https://www.salesforce.com", "detectedBy": ["dns"] },
        { "name": "Next.js", "version": "", "confidence": 100, "categories": ["JavaScript frameworks", "Web frameworks", "Web servers", "Static site generator"], "website": "https://nextjs.org", "detectedBy": ["headers"] }
    ],
    "error": null,
    "scannedAt": "2026-09-23T20:35:06.741Z"
}

Summary columns: cms, ecommerce, analytics, tagManagers, advertising, marketingAutomation, crm, liveChat, emailHosting, emailSending, payments, cdn, hosting, webServer, frameworks, programmingLanguages, security, ai. The full per-category breakdown is in byCategory.

Failed websites come back with "status": "error" and an error code (DNS_NOT_FOUND, TIMEOUT, CONNECTION_FAILED, INVALID_INPUT, BLOCKED_ADDRESS, TOO_MANY_REDIRECTS), and they are not charged.

How it detects technologies

For each website it fetches the homepage (following redirects) and matches fingerprints against:

• HTTP headers and cookies
• HTML, meta tags, script URLs, inline scripts and page structure (CSS selectors)
• DNS: MX, TXT (SPF includes and domain-verification records), NS, SOA, CNAME

Detections come with a confidence score (0-100). Implied technologies are added too (e.g. WordPress → PHP, MySQL), and are marked detectedBy: ["implied"]. Use Minimum confidence to drop weaker signals.

Limitations (so you know what you're getting)

• No browser rendering. Technologies that only show up after JavaScript runs in a browser (some tags injected by tag managers, for example) can be missed. In exchange, the Actor is much faster and cheaper than browser-based detectors.
• Bot-protected websites may answer with a block page (HTTP 403). You still get the full DNS stack and the protection vendor (Cloudflare, DataDome, Akamai…), and the result shows the real httpStatus.
• DNS records show that a company has set up a tool (e.g. verified its domain with it). Usually that means they use it, but not always today.

FAQ

Is it a Wappalyzer or BuiltWith alternative? Yes. It uses the open-source Wappalyzer fingerprint format and data, plus DNS-based SaaS detection that Wappalyzer's browser extension doesn't do.

Can I use it via API? Yes. Like every Apify Actor, you can run it via the Apify API, schedule it, or connect it to Make, Zapier, n8n, Google Sheets and others.

Is it legal? It only reads public information: a website's public homepage and public DNS records, the same things a browser or dig sees.

Credits and license

Technology fingerprints: enthec/webappanalyzer (GPL-3.0), a community-maintained continuation of the open-source Wappalyzer dataset. This Actor is licensed GPL-3.0.