Data & Diagnostics // Online

Tech Stack Checker.

A tech stack checker scans any website's public signals to identify the technologies powering it. Enter a domain and this free tool inspects HTTP response headers, JavaScript script tags, meta generator tags, cookie names, inline code patterns, and DNS records to detect frontend frameworks like React or Next.js, analytics platforms like Google Analytics, CDN providers like Cloudflare, CMS systems like WordPress, server software like Nginx, and dozens more. Each detection includes a confidence rating — confirmed, likely, or possible — based on the strength and number of matching signals found.

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Enter any domain to detect its technology stack via HTTP headers, scripts, and DNS records.
How to Use

Get Started in 3 Steps

Step 01

Enter a Domain

Type any domain name (e.g., stripe.com, shopify.com). The tool accepts bare domains, full URLs, and email addresses — it extracts the domain automatically.

Step 02

View Detected Technologies

See all identified technologies grouped by category — frontend frameworks, analytics, CDN, server, and more — each with a confidence rating and matched signal count.

Step 03

Analyze the Stack

Use the results to understand a company's technical decisions, identify sales opportunities, benchmark against competitors, or audit your own site's technology footprint.

How It Works

Under the Hood

When you submit a domain, the tool fetches the homepage over HTTPS with a 5-second timeout and 512KB body limit. It follows up to three redirects, re-validating each hop against SSRF protections to ensure only public IPs are contacted.

The response is parsed to extract four signal types: HTTP headers (Server, X-Powered-By, X-Generator), HTML elements (script src URLs, meta tags, inline patterns like data-reactroot or __NEXT_DATA__), and cookie names associated with specific platforms.

In parallel, the tool queries DNS-over-HTTPS for TXT and CNAME records, which reveal additional technologies — for example, SPF records mentioning Google indicate Google Workspace, while CNAME records pointing to cdn.shopify.com confirm Shopify hosting.

All extracted signals are matched against a database of 90+ technology fingerprints. Each match is scored by signal strength (strong, moderate, weak) and the confidence algorithm assigns confirmed, likely, or possible ratings based on the number and quality of matches.

FAQ

Frequently Asked Questions

What technologies can this tool detect on a website?
The Tech Stack Checker detects frontend frameworks (React, Vue, Angular, Next.js), analytics platforms (Google Analytics, Hotjar, Segment), CDNs (Cloudflare, Fastly, AWS CloudFront), CMS platforms (WordPress, Shopify, Webflow), server software (Nginx, Apache, Express), JavaScript libraries (jQuery, Bootstrap, Tailwind CSS), payment processors (Stripe, PayPal), marketing tools (HubSpot, Intercom), and security services. It analyzes HTTP response headers, HTML script tags, meta tags, cookies, inline code patterns, and DNS records to identify over 90 technologies.
How does the Tech Stack Checker work?
When you enter a domain, the tool fetches the homepage over HTTPS and analyzes multiple signals in parallel. It inspects HTTP response headers like X-Powered-By and Server, scans script src URLs for known library patterns, checks meta generator tags, examines cookie names associated with specific platforms, searches for inline code fingerprints like __NEXT_DATA__ or data-reactroot, and queries DNS TXT and CNAME records. Each detected technology receives a confidence rating based on the number and strength of matching signals.
What do the confidence levels mean?
Each detected technology gets a confidence level: Confirmed means two or more signals were detected or one strong signal was found — the technology is almost certainly present. Likely means exactly one moderate-strength signal matched, such as a script URL pattern. Possible means only weak signals were detected, which could indicate the technology is present but the evidence is less conclusive. Strong signals include specific response headers and unique HTML attributes, while weak signals are more generic patterns.
Can I check any website or are there restrictions?
You can check any publicly accessible domain that serves content over HTTPS. The tool cannot analyze sites behind authentication walls, sites that block automated requests, or domains that resolve to private or reserved IP addresses. If a site uses a Web Application Firewall that blocks our requests, results may be incomplete. For best results, check domains with publicly accessible homepages. The free tier allows 5 checks per hour, and entering your work email unlocks 20 checks per hour.
How can I use tech stack data in my sales or marketing strategy?
Technology data helps you prioritize outreach and personalize messaging. If a prospect uses an older CMS or lacks a CDN, you can position relevant solutions. Knowing a company runs React plus Stripe suggests a modern SaaS product with specific infrastructure needs. Sales teams use tech stack intelligence to identify companies using competitor products, find prospects with complementary technology needs, and qualify leads based on technical sophistication. Combine tech stack data with firmographic data for richer ideal customer profiles.
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