Tech Stack Detector – Bulk Wappalyzer Alternative

Tech Stack Detector finds out what any website is built with. Paste a list of domains and get one spreadsheet row per site: CMS, ecommerce platform, analytics and ad pixels, CDN, hosting, JavaScript frameworks, payment providers and chat widgets, matched against 7,600+ Wappalyzer-format fingerprints. A pay-as-you-go bulk tech stack lookup and Wappalyzer / BuiltWith alternative: no subscription, no API key.

Try it in one click: the input is prefilled with three sites. Press Start and you'll have results in under a minute. Apify's free plan covers about 1,200 sites a month.

What data does the tech stack lookup return?

domain	cms	ecommerce	javascriptFrameworks	cdn / hosting	technologies
wordpress.org	WordPress 7.2				13
allbirds.com	Shopify	Shopify		Cloudflare	10
nextjs.org			Next.js, React	Vercel	10

Plus 21 category columns (analytics, advertising, live chat, payment processors, tag managers, web servers…), a technologies array with version, confidence and the signal that found each one, and a clear error code for sites that couldn't be scanned (not charged).

How to detect a website's technology in 3 steps

1. Paste domains or URLs into Websites to analyse, one per line (or comma-separated). A whole spreadsheet column works; duplicates, blank lines and www. variants are cleaned up, and typos like htps:// are fixed.
2. Leave Deep scan off for the fast, cheap scan, or turn it on to also catch analytics, ad pixels and chat tools that only load with JavaScript.
3. Click Start, then download CSV, Excel or JSON, or call it from the API, Make, Zapier or n8n.

How much does it cost to look up a tech stack?

$4 per 1,000 sites scanned, so Apify's $5 monthly free credit covers about 1,250 sites with the fast scan. Deep scan adds $3 per 1,000 sites opened in the browser. Sites that fail (no DNS, timeouts, blocked, bot checks) are free. Scanning 500 domains with the fast scan costs about $2. Set a maximum cost per run, and the actor stops cleanly when it's reached.

Who uses a bulk technology lookup?

• Lead lists. Which of these 5,000 stores run Shopify? Which sites use HubSpot, Klaviyo or Intercom? Filter a prospect list down to the companies that use (or don't use) a given tool.
• Competitor research. See the analytics, A/B testing, chat and payment tools behind competitors' sites.
• Market sizing. Count how many sites in a niche use WordPress vs. Webflow vs. Wix.
• Agencies and freelancers. Qualify prospects before a call: "they're on WooCommerce with an old jQuery".
• Security and IT inventory. Detect server software and framework versions across your own domains.

Fast scan or deep scan?

	Fast scan (default)	Deep scan (browserMode: always)
How	One normal HTTP request per site	The fast scan, then the page is opened in headless Chrome
Finds	CMS, ecommerce platform, web server, CDN, hosting, most frameworks	All of that, plus tools that only load at runtime: analytics, ad pixels, chat, A/B testing, JS libraries
Technologies per site (our test set)	median 10	median 16
Speed on Apify	about 40 sites a minute	about 10 sites in 2–2.5 minutes (2 GB)

Auto mode sits in between: it opens the browser only for sites where the fast scan is blocked or finds fewer than 5 technologies.

Input example

{
  "domains": ["wordpress.org", "allbirds.com", "https://www.bbc.co.uk"],
  "browserMode": "off",
  "minConfidence": 0
}

Output

One row per site. The technologyNames text and the category columns paste cleanly into a spreadsheet, and the technologies array has the full detail.

{
  "input": "wordpress.org",
  "domain": "wordpress.org",
  "url": "https://wordpress.org/",
  "statusCode": 200,
  "scanMethod": "http",
  "title": "Blog Tool, Publishing Platform, and CMS – WordPress.org",
  "technologyCount": 13,
  "technologyNames": "Google Tag Manager, Gutenberg 24.1.0, HSTS, MySQL, Nginx, Open Graph, PHP, WordPress 7.2, ...",
  "technologies": [
    { "name": "WordPress", "version": "7.2", "categories": ["CMS", "Blogs"], "confidence": 100, "website": "https://wordpress.org", "detectedBy": "header" }
  ],
  "cms": "WordPress 7.2, WordPress Block Editor, WordPress Site Editor",
  "ecommerce": "",
  "analytics": "",
  "tagManagers": "Google Tag Manager",
  "webServers": "Nginx",
  "programmingLanguages": "PHP",
  "databases": "MySQL",
  "cdn": "",
  "hosting": "",
  "error": null,
  "errorCode": null,
  "scannedAt": "2026-10-05T16:13:02.114Z"
}

Category columns: cms, ecommerce, analytics, tagManagers, advertising, marketingAutomation, liveChat, paymentProcessors, javascriptFrameworks, javascriptLibraries, webFrameworks, programmingLanguages, databases, webServers, cdn, hosting, security, cookieCompliance, reviews, fonts, other.

detectedBy says which signal identified the technology: header, cookie, html, script, css, meta, dom, js (deep scan only) or implied (for example, WordPress implies PHP).

Sites that can't be scanned still get a row, with error and errorCode filled in (DNS, TIMEOUT, HTTP_BLOCKED, BOT_CHALLENGE, HTTP_ERROR, TOO_MANY_REDIRECTS, ROBOTS_DISALLOWED, TLS, NETWORK). BOT_CHALLENGE means the site answered with a bot check or waiting-room page (Cloudflare, Akamai, DataDome and similar) instead of its homepage. Error rows have no technologies (technologyCount is 0), because what we saw was the block page, not the site; the error text names the bot wall when we recognise it. If the fast scan was blocked, the error suggests trying Deep scan Auto, which often gets through. You aren't charged for these rows.

Input lines that aren't web addresses (allbirds, not a url) also get a row, with errorCode: "INVALID_INPUT" and the line echoed in input and domain, so every line you pasted comes back. They're free, and the status counts them: "Analysed 2 of 4 entries; 2 weren't web addresses".

The run's OUTPUT record in the key-value store has a summary: how many sites were scanned, loaded, failed or skipped, and which input lines weren't valid domains.

How it works, and how it behaves on the web

• Each site gets one visit to its public homepage (or the URL you gave), plus a request for its robots.txt. No crawling, no logins, nothing behind a paywall, and no personal data collected.
• It respects robots.txt. If a site's robots.txt disallows its homepage for automated visitors, the site is skipped and reported as ROBOTS_DISALLOWED.
• It identifies itself honestly with the user agent TechStackDetectorBot.
• Detection uses the open-source Wappalyzer-format fingerprints maintained by ProjectDiscovery (wappalyzergo, MIT licence), matched against response headers, cookies, HTML, script URLs, inline scripts and styles, meta tags and DOM selectors, and, in deep scan, JavaScript globals in the live page. Fingerprints come from wappalyzergo, last refreshed 2026-10-04 (refreshed by hand, not on a schedule).

Accuracy

On a test set of 38 well-known sites with publicly known stacks, the fast scan found 85% of the expected core technologies (CMS, platform, framework), and the deep scan found 92%. What it can't see:

• Back-end-only technology that leaves no trace in the page (for example a Django site with no forms on its homepage).
• Sites that block automated visitors entirely (HTTP 403 to every client).
• Styles in external CSS files. CSS-only fingerprints (Tailwind CSS, for example) are matched only against styles inlined in the page.

As with any fingerprint-based detector, low-confidence hints can occasionally be wrong. Set Minimum confidence to 50 or more if you want only strong matches.

Ready-made examples

Each one opens this actor with the input already filled in. Click Try to run it, or change the input to fit your own list.

• Is it WordPress? Bulk CMS checker
• Check which Shopify stores use Klaviyo
• Which ecommerce platform does a store use?
• Tech stack of SaaS competitors
• Check Google Analytics and Tag Manager on websites
• Detect Next.js and React websites

More tools from oldjard

• Sitemap URL Extractor: every URL on a website, for RAG and SEO.
• Shopify Products Scraper & Price Monitor: catalogs and price changes from any Shopify store.
• Workday, Greenhouse, Lever & Ashby Jobs Scraper: every open job from company career sites.
• Bulk Website Screenshot & URL to PDF: screenshots and PDFs of any list of pages.
• AI Web Scraper (your own key): describe fields in English, get JSON.
• Website Change Monitor: a before/after diff by webhook, Slack or Discord when a page changes.
• Company Registry Lookup: UK Companies House, Spain, France, Finland and Norway in one schema.
• UK & EU Public Tenders: Find a Tender and TED notices in one table, with daily only-new alerts.

Use it from an AI agent or the API

• Minimal input: {"domains": ["example.com"]}. Everything else has a sensible default.
• Cost: $0.004 per website analysed, plus $0.003 per site opened in the browser (browserMode auto or always). Sites that fail to load are free. 100 sites with the fast scan ≈ $0.40.
• Run time (our runs): 10 sites with the fast scan in 6–24 s. Deep scan works at the default 1 GB but opens one page at a time there; give the run 2 GB or more to render several sites at once.
• Results: the default dataset, one row per site (a technologies array plus category columns); the run summary is the OUTPUT record in the key-value store.
• Works over the Apify MCP server (search-actors, then call-actor) and is eligible for agentic payments (x402).

FAQ

Is this the official Wappalyzer or BuiltWith? No. It's an independent tool that uses an open-source, Wappalyzer-compatible fingerprint set. It isn't affiliated with Wappalyzer or BuiltWith.

How is this different from BuiltWith? BuiltWith keeps a historical database you search by technology. This actor checks the live site right now, from a list you give it, and charges per site with no subscription.

Does it look up historical technology? No, it reports what a site runs right now.

Can I scan specific pages, not just homepages? Yes, give a full URL such as https://example.com/pricing.

How many domains per run? As many as you like. Large lists run at up to 50 sites in parallel (5 in the browser).

Can I run it on a schedule? Yes. Save your input as a task and schedule it in Apify to track stack changes over time.

Feedback

Found a technology it misses or gets wrong? Open an issue on the Issues tab with the domain and what you expected. It helps us improve detection for everyone.