How to Find What Technology a Website Uses (Tech Stack Checker Guide)

Every website leaves technological fingerprints. The JavaScript frameworks loading in the browser, the HTTP headers sent by the server, the meta tags in the HTML — all reveal what technology stack a website runs on. Knowing your competitors' tech stacks provides surprisingly valuable strategic intelligence.

Why Tech Stack Detection Matters

Understanding a competitor's technology choices tells you:

• Their investment level — Custom-built platforms signal serious engineering investment; WordPress signals speed-to-market priority
• Their capabilities — The tools they use hint at what features they can (and cannot) build
• Their scaling readiness — Infrastructure choices reveal whether they are prepared for growth
• Sales intelligence — Knowing prospects' tech stacks helps tailor your pitch
• Hiring signals — Job postings mentioning specific technologies confirm detected stacks

Method 1: Browser Extensions

Wappalyzer

Wappalyzer is the most popular tech detection browser extension, available for Chrome and Firefox. Visit any website and click the Wappalyzer icon to see a categorized list of detected technologies: CMS, JavaScript frameworks, analytics, advertising, hosting, and more.

Detects: 1,700+ technologies across 100 categories

Free tier: Unlimited lookups for individual sites

BuiltWith Browser Extension

BuiltWith's extension provides similar detection with additional market share data and technology relationships. It shows not just what a site uses but how popular each technology is across the web.

Method 2: Online Lookup Tools

BuiltWith.com

BuiltWith's web interface provides the deepest free tech lookup available. Enter any URL and get a comprehensive breakdown including:

• Analytics and tracking tools
• Hosting provider and CDN
• CMS and framework
• JavaScript libraries
• SSL certificate provider
• Payment processors
• Email service providers
• A/B testing tools

W3Techs

W3Techs provides technology usage statistics and trends across the entire web. Useful for understanding market share of different technologies and identifying industry-standard choices versus niche selections.

BenchSpy

BenchSpy includes tech stack detection as part of its competitive analysis. The advantage over standalone tools is context — it shows how technology choices correlate with a competitor's performance, content strategy, and overall digital sophistication.

Method 3: Manual Detection Techniques

For more thorough investigation, you can manually detect technologies:

View Page Source

Right-click on any webpage and select "View Page Source." Look for:

• Meta generator tags — <meta name="generator" content="WordPress 6.7">
• CSS/JS file paths — /wp-content/ indicates WordPress; /_next/ indicates Next.js
• Script tags — Google Analytics, Facebook Pixel, and other tracking scripts are clearly visible
• Comments — Developers sometimes leave framework identifiers in HTML comments

Check HTTP Headers

Browser DevTools (F12 > Network tab) reveal server headers that identify:

• Server — Apache, Nginx, IIS, or cloud platforms
• X-Powered-By — PHP version, Express.js, ASP.NET
• X-Cache — CDN information (Cloudflare, Fastly, CloudFront)
• Set-Cookie — Cookie names often reveal CMS platforms

Check DNS Records

DNS lookups reveal hosting providers and email services:

• A records — Point to hosting IP addresses (identifiable via IP lookup)
• MX records — Email service (Google Workspace, Microsoft 365, custom)
• CNAME records — Often reveal CDN and SaaS integrations
• TXT records — Verification records for services like Google, HubSpot, and Mailchimp

Method 4: JavaScript Detection

Open browser DevTools console and try these checks:

• window.React — React.js
• window.Vue — Vue.js
• window.angular — AngularJS
• window.jQuery — jQuery
• window.Shopify — Shopify
• window.ga — Google Analytics (Universal)
• window.gtag — Google Analytics (GA4)
• window.fbq — Facebook Pixel

What Each Technology Category Reveals

CMS Choice

• WordPress — Prioritizes content creation speed and plugin ecosystem. Most flexible but requires maintenance.
• Webflow — Design-focused, likely a smaller team without dedicated developers.
• Custom-built (React/Next.js) — Significant engineering investment, likely a tech-forward company.
• Shopify — Ecommerce-focused, standardized commerce infrastructure.

Analytics and Marketing Tools

• Google Analytics only — Basic analytics setup, common for smaller operations.
• Mixpanel/Amplitude — Product-led growth, focused on user behavior analysis.
• HubSpot — Inbound marketing-focused, likely running content marketing and email campaigns.
• Intercom/Drift — Sales-assisted growth, prioritizing conversations and support.

Infrastructure

• AWS/GCP/Azure — Scalable cloud infrastructure, serious about growth.
• Shared hosting — Early stage, limited technical resources.
• Vercel/Netlify — Modern frontend deployment, developer-focused team.

Using Tech Stack Intelligence Strategically

For Competitive Analysis

If a competitor recently added Intercom and HubSpot, they are investing in lead generation and support — expect more aggressive marketing. If they switched from WordPress to a custom platform, they are investing in product differentiation.

For Sales Prospecting

If you sell a developer tool, target companies using technologies your tool integrates with. Tech stack data helps qualify leads before outreach.

For Product Development

If competitors all use a particular technology and you do not, consider whether you are missing something or whether you have a differentiation opportunity.

For automated tech stack detection as part of a comprehensive competitive analysis, try BenchSpy free. It identifies competitor technologies and connects them to broader strategic insights.