Free BuiltWith Alternatives in 2026: 5 Tools That Won't Cost You $295/Month

BuiltWith is the gold standard for website technology detection. It has the largest fingerprint database, historical data going back years, and built-in lead list generation. But its Basic plan starts at $295/month, and API access requires the Pro plan at $995/month. For individual developers, freelancers, and small teams, that price is hard to justify.

The good news: you don't have to pay enterprise pricing to detect what technologies a website uses. Here are five alternatives that offer free tiers or significantly lower price points—and an honest look at what you give up compared to BuiltWith.

What You Actually Get with BuiltWith

Before we look at alternatives, it helps to understand why BuiltWith charges what it does. The $295/month isn't just for technology detection—it bundles several capabilities:

• 111,000+ technology signatures: The largest database by far, covering obscure analytics snippets, A/B testing tools, and ad networks that no other service tracks.
• Historical data: Technology usage history going back years. You can see exactly when a site migrated from Angular to React, or when they added Stripe.
• Lead list generation: Filter and export prospect lists by technology stack (e.g., "all Shopify stores using Klaviyo in the US").
• Market share reports: Aggregate statistics on technology adoption across millions of crawled sites.

If you need all four of those capabilities—especially historical data and lead lists—BuiltWith is genuinely hard to replace. But if you mainly need to detect what tech a site is running right now, these alternatives cover that at a fraction of the cost.

1. DetectZeStack — API-First Detection with a Free Tier

Price: Free (100 requests/month), paid plans from $9/month (1,000 requests) to $79/month (50,000 requests).

DetectZeStack is a REST API built for developers who need programmatic technology detection without enterprise pricing. Every plan—including the free tier—gets full API access with the same endpoints and response format.

What makes it different from other detection tools is the multi-layer approach. Beyond standard HTTP header and HTML fingerprinting, DetectZeStack inspects DNS CNAME records and TLS certificates to identify infrastructure that browser-based tools completely miss—CDN providers like Cloudflare and Fastly, hosting platforms like Netlify and Vercel, and certificate authorities like Let's Encrypt and DigiCert.

On the application layer, it detects WordPress installations (including themes and plugins), JavaScript frameworks like React, Vue, and Angular, and e-commerce platforms like Shopify and WooCommerce—all from a single API call.

It also includes CPE identifiers for detected technologies when available, mapping directly to the NVD vulnerability database. And the /changes endpoint tracks technology additions, removals, and version changes over time—a capability BuiltWith charges $295/month for.

2. Wappalyzer — Free Browser Extension, Paid API

Price: Browser extension is free. API starts at $100/month (Starter), $250/month (Pro).

Wappalyzer is the most recognized name in tech detection after BuiltWith. Its Chrome and Firefox extension lets you click an icon and instantly see what technologies the current page uses. For manual, one-at-a-time lookups, the free extension works well.

The catch is the API. If you need programmatic access, Wappalyzer's Starter plan costs $100/month—and credits expire after 60 days. That means if you buy a block of API credits in January and don't use them all, they vanish by March. The Pro plan at $250/month has the same expiration policy.

Wappalyzer closed its open-source repository in August 2023 after being acquired by Sindup. The fingerprint database is no longer community-maintained, and self-hosting is no longer an option with updated signatures.

3. WhatRuns — Free Browser Extension, No API

Price: Free.

WhatRuns is a free Chrome extension that detects technologies on any page you visit. It covers frameworks, CMS platforms, analytics tools, and hosting providers. The interface is clean, and detection quality is reasonable for major technologies.

The limitation is simple: there's no API. WhatRuns is a browser extension only. You can't integrate it into scripts, pipelines, or automated workflows. There's no batch analysis, no change tracking, and no way to export results programmatically. The founder appears to have moved on to other projects, so development has slowed.

For a deeper comparison, see DetectZeStack vs WhatRuns.

4. Netcraft — Free Site Reports for Security Checks

Price: Free for basic site reports. Enterprise pricing for bulk access and API.

Netcraft's Site Report tool lets you look up basic information about any website for free—server software, hosting provider, DNS records, SSL certificate details, and risk ratings. It's been around since 1995 and has a strong reputation in the security community.

The free tool is useful for quick security-oriented checks, but it's limited. You get one site at a time through a web form, with no API access on the free tier. Netcraft's commercial offerings (anti-phishing, brand protection, bulk data) are enterprise-priced and not publicly listed—you need to contact their sales team.

Netcraft is not a direct BuiltWith replacement. It focuses on infrastructure and security rather than application-layer technology detection. It won't tell you if a site uses React or Vue, but it will identify the web server, hosting provider, and certificate authority.

5. Self-Hosting wappalyzergo (Open Source)

Price: Free (open source), but requires your own infrastructure.

Before Wappalyzer closed its source, the community created wappalyzergo—a Go implementation of the Wappalyzer fingerprinting engine. It's still available on GitHub and can be self-hosted. You can integrate it into your own Go applications or run it as a service.

The tradeoff is maintenance. The fingerprint database in wappalyzergo is a snapshot from the last open-source Wappalyzer release. New technologies, framework updates, and SaaS tools launched since August 2023 won't be detected unless someone manually adds signatures. You also need to handle infrastructure—hosting, scaling, rate limiting, and caching—yourself.

Self-hosting wappalyzergo gives you HTTP-based detection only. There's no DNS analysis, no TLS certificate inspection, and no CPE mapping unless you build those layers yourself. For more on this, see Wappalyzer Went Closed Source: What Changed and What to Use Instead.

Comparison Table

What You Lose Compared to BuiltWith

None of these alternatives fully replace BuiltWith. Here's what you're giving up:

• Historical data archives: BuiltWith stores technology snapshots going back years. You can see when a site adopted or dropped a technology months or years ago. DetectZeStack tracks changes going forward (up to 365 days of history), but doesn't have retroactive data from before you started monitoring.
• Lead list generation: BuiltWith's core value for sales teams is the ability to filter its database by technology and export prospect lists (e.g., "all sites using Salesforce in the UK"). None of the alternatives listed here offer this.
• Market share reports: BuiltWith regularly crawls millions of sites and publishes aggregate statistics on technology adoption. This is useful for competitive intelligence and market research. No free alternative provides this at the same scale.
• Signature breadth: BuiltWith tracks over 111,000 technologies. The alternatives here cover 7,000–8,000 at most. Major frameworks, CMS platforms, CDNs, and analytics tools are well covered, but niche widgets and obscure plugins may be missed.

When BuiltWith Is Actually Worth It

To be fair, there are cases where $295/month (or more) is justified:

• Enterprise sales teams that need technology-filtered prospect lists to target companies using specific tools. If a lead list helps you close one deal, the tool pays for itself.
• Market researchers who need historical technology adoption data across millions of sites for reports and trend analysis.
• Organizations with $10K+/year tooling budgets where $3,500/year for BuiltWith Basic is a rounding error compared to the value of the data.

If those describe you, BuiltWith is the right choice. For our full breakdown of BuiltWith vs other tools, see BuiltWith vs Wappalyzer vs DetectZeStack.

But if you're a developer building an integration, a freelancer checking a client's stack, a security engineer running audits, or a small team that needs API access without an enterprise budget—one of the five alternatives above will get you there.

Which Alternative Should You Pick?

For most developers and small teams, the practical choice comes down to DetectZeStack for API access or Wappalyzer's free extension for manual checks. You can read the getting started guide to see how the API works in practice.