Website Tech Stack Detector — Technology Lookup & Public DNS SaaS Discovery

What it does

A bulk tech stack detector and technology lookup for public websites. This BuiltWith alternative and Wappalyzer alternative combines homepage fingerprints with public DNS to help answer what CMS is this site using, discover email infrastructure, and identify SaaS verification signals invisible on the homepage.

• 206 independently authored technology fingerprints; no licensed Wappalyzer or BuiltWith database.
• Homepage HTML, script/link URLs, response headers, cookie names, and meta generator.
• Public MX, TXT/SPF, NS and CNAME records, with Cloudflare DNS-over-HTTPS and Google fallback.
• Evidence and confidence per detection, CSV-friendly names and category groups.
• Robots.txt respected by default, bounded body size and concurrency; no browser required.

Detected categories

Categories	Examples
CMS / Ecommerce / Website builder	WordPress, Drupal, Shopify, WooCommerce, Wix, Webflow
JavaScript framework / Web framework / JS library / UI framework	Next.js, Nuxt, Express, ASP.NET, jQuery, Bootstrap
Analytics / Tag manager / Advertising/pixels / A/B testing	Plausible, Google Tag Manager, Meta Pixel, Optimizely
Marketing automation / CRM	HubSpot, Klaviyo; verification signals complement visible CRM integrations
Email delivery / Email hosting	SendGrid, Mailgun, Amazon SES, Google Workspace, Microsoft 365
Live chat/support / Payments	Intercom, Zendesk, Stripe, PayPal
CDN / Hosting/PaaS / DNS provider / Web server / Security/WAF	Cloudflare, Vercel, Route 53, nginx
Consent/cookie banner / Fonts / Video / Search	OneTrust, Google Fonts, Vimeo, Algolia
Reviews / Forms / Scheduling	Trustpilot, Typeform, Calendly
Domain verification (SaaS used)	Atlassian, OpenAI, Zoom, Adobe, Slack

Use cases

• Lead qualification and sales prospecting lists: find websites using Shopify / HubSpot within your supplied domain list.
• Competitor research and agency technology audits.
• Market share studies across your own representative domain samples.
• Enriching CRM with email provider lookup and SaaS infrastructure hints.

Input

Field	Default	Description
domains	wordpress.org, stripe.com, shopify.com	Array of domains or URLs; normalized and deduplicated. Invalid lines skipped, not billed.
checkHomepage	true	HTTPS homepage GET, at most 2 MB, up to five redirects; HTTP fallback on connection/TLS failure.
respectRobotsTxt	true	Skip homepage if root is disallowed for our UA or wildcard. DNS checks continue.
checkDns	true	Public MX, TXT, NS and CNAME lookup.
categories	[]	Optional category allowlist; empty returns all.
maxConcurrency	5	Domain workers, 1–20.
timeoutSecs	20	Per-request timeout, 1–60 seconds.

{"domains":["shopify.com","https://wordpress.org/","stripe.com"],"checkDns":true,"checkHomepage":true,"maxConcurrency":5}

Output

One item per processed, valid, unique domain; failed checks still produce a billed row.

{"domain":"example.com","inputValue":"https://example.com/","finalUrl":"https://example.com/","httpStatus":200,"title":"Example store","technologies":[{"name":"Shopify","category":"Ecommerce","version":null,"confidence":"high","evidence":"scriptSrc: cdn.shopify.com/","website":"https://shopify.com"}],"technologyNames":["Shopify"],"categories":{"Ecommerce":["Shopify"]},"emailProvider":null,"dnsProvider":null,"hosting":null,"cdn":null,"homepageSkipped":null,"error":null,"errorMessage":null,"checkedAt":"2026-11-08T00:00:00+00:00"}

Field	Description
domain / inputValue	Normalized hostname and first supplied value.
finalUrl / httpStatus / title	Final homepage URL, status, and trimmed title; null when not fetched.
technologies	Name, category, version (if captured), high/medium confidence, short evidence and vendor website.
technologyNames / categories	Flat names for CSV filtering and category-to-names mapping.
emailProvider / dnsProvider / hosting / cdn	Best guesses from all detections, including when categories are filtered. MX gateways may hide the underlying mailbox provider.
homepageSkipped	null, robots_txt, or fetch_failed.
error / errorMessage	Error when enabled checks cannot complete; domain_not_found identifies NXDOMAIN, timeout identifies the wall-clock cap, and internal_error isolates unexpected errors. DNS-only detections survive homepage failures.
checkedAt	UTC timestamp.

Pricing

You pay only for domains saved to the dataset, plus a tiny per-run start fee; Apify platform usage is included in the price. Duplicate domains and truly invalid input lines are not saved or billed. A valid domain with failed network checks still has a saved result and is billed. Processing stops normally when the dataset event-charge limit is reached. The current price per 1,000 domains is shown on the Pricing tab of this page.

Tips / limits

Detection means fingerprints, not a comprehensive inventory or proof of a paid subscription. Verification records may be stale or represent a free service; SPF indicates authorized senders, not necessarily current use. Generic verification tokens do not establish a specific Google or Microsoft product. Homepage-only analysis does not execute JavaScript and may miss technologies loaded after interaction. Vendor CDN URLs can identify embedded integrations rather than the site's primary platform. Subdomains use their own DNS records; submit the company apex for email provider lookup. DNS CNAME flattening can hide hosting hints. HTTP errors, robots restrictions and anti-bot pages reduce recall. No CAPTCHA solving or anti-bot bypass. Rate limits and transient errors retry up to three total attempts with backoff and Retry-After (capped at 30 seconds). Each domain has a 120-second wall-clock cap.

Compliance & data source

Only public homepages, robots.txt and official public DNS-over-HTTPS endpoints are accessed, with User-Agent EchoLab-Apify-Actor/tech-stack-detector (+https://apify.com/echolab). No login, personal contact extraction, cookie values or raw verification tokens are output. Titles redact email addresses and phone-like strings; do not submit credential-bearing URLs or URLs containing personal data. Users are responsible for complying with each source's terms and applicable laws.

Support

Open an issue on the Actor's Issues tab.

More real output, worked pricing examples and a comparison with alternatives: https://echolab-tools.pages.dev/tech-stack-detector/