Free Tech Stack Analyzer

The CompetLab Tech Stack Analyzer is a free web-based tech stack detector for B2B SaaS competitive research. Enter any domain; it fetches the site's public homepage once, runs 117 declarative detection rules against the HTML and HTTP response headers, and returns a categorized report of every detected technology with evidence.

Specifically, the tool:

• Detects hosting providers, CDNs, frameworks, content management systems, authentication providers, payment processors, and cookie-consent platforms
• Detects analytics tools, tag managers, session recording platforms, marketing automation, CRM, advertising pixels, and A/B testing tools
• Detects customer support tools, form builders, video hosting, and application monitoring platforms
• Shows the exact HTML snippet, meta tag, script URL, or response header that matched for every detected technology
• Groups detections into three business-intent categories (Tech Stack, Growth Stack, Engagement Stack) instead of a flat alphabetical list
• Works free with no account required and no paywall on detection detail

Several free tools identify website technologies. They differ substantially in what's free, how results are presented, and whether detections are verifiable.

The CompetLab Tech Stack Analyzer is built for users who need verifiable results, anonymous lookups without signup, and a categorization scheme that maps to how B2B SaaS teams think about their stack — free, no credit card, evidence inline under every detection.

Three clear user types get the most value from this tool.

Sales qualifies accounts by infrastructure fit; a prospect running Salesforce, Segment, and Marketo looks very different from one running HubSpot and Google Analytics. Engineering benchmarks architecture choices before a migration; if three competitors moved to Next.js in the last year, that is a signal. Product marketing and strategy read the Growth Stack to reverse-engineer a competitor's go-to-market motion.

Heavy ads-pixel density means paid-heavy acquisition. CDPs plus session recording means a conversion-optimization focus. Multiple experimentation tools mean an engineering-led product culture. The stack tells you where the money and engineering hours are going, without them telling you.

Tech stack detectors inspect two public surfaces: the HTML source of a page and the HTTP response headers returned by the server. A detection rule is just a declarative pattern. If the HTML contains <script src="js.stripe.com/v3/">, that site is using Stripe. This tool runs 117 rules on a single fetch.

What it cannot see: databases, server-side languages that do not leak via headers, internal microservices, background infrastructure, or anything that fires only after authentication. A lean result does not always mean a simple site. It often means a sophisticated one that strips identifying signals on purpose. False positives are rare but possible, which is why every detection in this tool comes with the exact matcher that fired. You can verify every result yourself.

This tool shows a snapshot. The real signal compounds in the diff. When a competitor swaps Intercom for Zendesk, it usually means support is restructuring or the customer base shifted from SMB to mid-market. When Stripe Billing appears, they are monetizing a new motion, often a self-serve plan launch that has not been announced yet. When a new CDP shows up, a data infrastructure project finished and a personalization push is imminent. When WordPress disappears and Next.js appears, marketing just got a new head and the site is being rebuilt.

These changes typically lead public announcements by two to eight weeks. This free tool will not tell you any of that. You would have to re-scan every competitor every day and diff the results yourself. That is what CompetLab does automatically, across pricing, positioning, content, and AI visibility.

1. Enter any domain. Paste a URL and click Analyze Stack. The tool fetches the public homepage once, extracts the HTML and response headers, and runs 117 detection rules across hosting, frameworks, CMS, analytics, advertising, support, payments, and more.
2. Review the three stack categories. Results are grouped into Tech Stack, Growth Stack, and Engagement Stack. Each category reveals a different investment area: engineering, marketing, or customer experience.
3. Read the evidence on every detection. Each technology shows the exact pattern that matched up front — the script src, the meta generator, or the HTTP response header. No black box.
4. Spot the giveaway vendors. Payment processors, CDPs, and analytics platforms are your highest-signal finds. A site running Stripe Billing plus Segment plus HubSpot is running a mature revenue operation.
5. Check the growth stack for marketing maturity. Count the marketing tools. One tag manager plus one analytics tool is minimum viable. Add marketing automation, session recording, A/B testing, and retargeting pixels and you are looking at a well-resourced team.
6. Use the findings for sales, engineering, or strategy. Sales teams qualify accounts by fit. Engineering benchmarks architecture choices before a migration. Product marketing infers what ICP a competitor is targeting based on their CRM and analytics choices.
7. Run your competitors side by side. Analyze 3-5 competitors and compare their stacks across the three categories. Patterns emerge fast: who is investing in AI tooling, who is still on legacy infrastructure, who just added a new CDP.