---
title: "How to Detect What Technologies a Website Uses"
description: "How to detect CMS, JavaScript frameworks, libraries, and tools used on any website. An alternative to BuiltWith and Wappalyzer."
date: 2026-01-25
category: Web Development
tags: ["Technology Stack", "CMS Detection", "JavaScript", "Frameworks", "UPER SEO Auditor"]
url: https://uper.pl/en/blog/detect-website-technologies/
---

# How to Detect What Technologies a Website Uses

Wondering what your competitor's website is built on? Want to know what CMS a client uses before an audit? Or perhaps you're looking for technological inspiration? In this article, I'll show you how to detect the technology stack of any website.

## Why Detect Technologies?

Knowledge of the technology stack is useful in many situations:

- **Competitor analysis** - what powers their success
- **Before an audit** - tailoring recommendations to the platform
- **Client prospecting** - finding sites on specific CMS
- **Inspiration** - what industry leaders use
- **Security** - detecting outdated versions

## Popular Tools (and Their Limitations)

### BuiltWith

Extensive technology database, but:
- Requires account creation
- Full data is paid
- Slow web interface

### Wappalyzer

Popular browser extension:
- Good detection, but limited
- Separate tool from SEO audit
- Doesn't show context (versions, conflicts)

### DevTools

You can manually search the page source, but:
- Time-consuming
- Requires knowing what to look for
- Easy to miss things

## UPER SEO Auditor - Technology Detection

The [UPER SEO Auditor](https://chromewebstore.google.com/detail/uper-seo-auditor/khhpbeckpphaoiemjdijhbfpjnendage) extension automatically analyzes a website's technology stack in the **Stack** tab.

![UPER SEO Auditor - Technology Stack Detection](../../assets/images/blog/uper-seo-auditor-colors.png)

### Categories of Detected Technologies

| Category | Examples |
|----------|----------|
| **CMS** | WordPress, Drupal, Joomla, Shopify, Wix |
| **JS Frameworks** | React, Vue, Angular, Svelte, Next.js, Nuxt |
| **Libraries** | jQuery, Lodash, Moment.js, Axios |
| **CSS Frameworks** | Tailwind, Bootstrap, Bulma, Foundation |
| **Analytics** | GA4, GTM, Hotjar, Clarity, Plausible |
| **Advertising** | Google Ads, Facebook Pixel, LinkedIn |
| **CDN** | Cloudflare, Fastly, CloudFront, Akamai |
| **Hosting** | Netlify, Vercel, AWS, GCP |
| **E-commerce** | WooCommerce, Magento, PrestaShop |
| **Chat/Support** | Intercom, Zendesk, Tawk.to, Crisp |

### How Does It Work?

The extension analyzes:

1. **HTTP headers** - `X-Powered-By`, `Server`, custom headers
2. **Meta tags** - `generator`, viewport patterns
3. **Scripts** - paths, global variable names
4. **Styles** - CSS classes, comments
5. **Cookies** - platform-specific names
6. **DOM** - attributes, framework-specific structures

## CMS Detection

### WordPress

The extension detects WordPress through:

```html
<!-- Meta generator -->
<meta name="generator" content="WordPress 6.4.2">

<!-- Paths -->
/wp-content/themes/theme-name/
/wp-includes/js/jquery/

<!-- REST API -->
/wp-json/wp/v2/

<!-- Comments -->
<!-- This site is powered by WordPress -->
```

**Additional information:**
- WordPress version
- Active theme
- Detected plugins (Yoast, WooCommerce, Elementor)

### Shopify

```html
<!-- CDN -->
cdn.shopify.com/s/files/

<!-- Cookies -->
_shopify_s, _shopify_y

<!-- JavaScript -->
window.Shopify
```

### Other CMS Platforms

| CMS | Signals |
|-----|---------|
| Drupal | `/sites/default/files/`, `Drupal.settings` |
| Joomla | `/media/jui/`, `Joomla.optionsStorage` |
| Wix | `static.wixstatic.com`, `wix-code-sdk` |
| Squarespace | `static.squarespace.com` |
| Webflow | `webflow.com/api/`, `.w-` classes |
| Ghost | `ghost.io`, `ghost-` paths |

## JavaScript Framework Detection

### React

```javascript
// Global object
window.__REACT_DEVTOOLS_GLOBAL_HOOK__

// DOM attributes
data-reactroot
data-reactid

// Bundler chunks
/static/js/main.*.chunk.js
```

### Vue.js

```javascript
// Global object
window.__VUE__
window.__VUE_DEVTOOLS_GLOBAL_HOOK__

// Attributes
data-v-*
v-cloak
```

### Next.js

```html
<!-- Meta -->
<script id="__NEXT_DATA__">

<!-- Paths -->
/_next/static/
/_next/image
```

### Angular

```javascript
// Attributes
ng-version
_nghost-*
_ngcontent-*

// Global
window.ng
```

### Svelte / SvelteKit

```html
<!-- Classes -->
svelte-*
class="s-*"

<!-- Hydration -->
data-svelte-h
```

## Analytics Tools Detection

### Google Analytics 4

```javascript
// Script
gtag('config', 'G-XXXXXXX')

// Global object
window.dataLayer
window.gtag

// Request
google-analytics.com/g/collect
```

**Displayed information:**
- Measurement ID (G-XXXXXX)
- Enhanced Measurement enabled
- Debug mode

### Google Tag Manager

```javascript
// Script
googletagmanager.com/gtm.js?id=GTM-XXXXX

// Container
window.google_tag_manager
```

**Displayed information:**
- Container ID (GTM-XXXXX)
- Environment (live/preview)

### Other Trackers

| Tool | Detection |
|------|-----------|
| Hotjar | `static.hotjar.com`, `hj()` |
| Microsoft Clarity | `clarity.ms`, `window.clarity` |
| Plausible | `plausible.io/js/` |
| Fathom | `cdn.usefathom.com` |
| Matomo | `matomo.js`, `_paq` |

## Library Detection

### jQuery

```javascript
window.jQuery
window.$

// Version
jQuery.fn.jquery  // "3.7.1"
```

### Lodash / Underscore

```javascript
window._
window._.VERSION  // "4.17.21"
```

### Other Popular Libraries

| Library | Signal |
|---------|--------|
| Axios | `window.axios` |
| Moment.js | `window.moment` |
| Day.js | `window.dayjs` |
| GSAP | `window.gsap` |
| Three.js | `window.THREE` |
| D3.js | `window.d3` |

## CSS Frameworks

### Tailwind CSS

```html
<!-- Characteristic classes -->
class="flex items-center justify-between"
class="bg-blue-500 hover:bg-blue-700"
class="px-4 py-2 rounded-lg"
```

### Bootstrap

```html
<!-- Classes -->
class="container"
class="row col-md-6"
class="btn btn-primary"

<!-- CDN -->
cdn.jsdelivr.net/npm/bootstrap
```

### Bulma

```html
class="columns is-multiline"
class="button is-primary"
```

## Practical Applications

### 1. Before an SEO Audit

Knowing a site uses WordPress + Yoast:
- Check Yoast configuration
- Look for plugin conflicts
- Apply WP-specific recommendations

### 2. Competitor Analysis

Competitor outranking you? Check:
- What CMS they use
- Better analytics tools
- Performance solutions (CDN, lazy loading)

### 3. Detecting Outdated Technologies

Stack Detection can find:
- Old jQuery versions (security risk)
- Outdated frameworks
- Deprecated libraries

### 4. Estimating Migration Costs

Client wants a redesign? Knowing the site is:
- WordPress + WooCommerce + 20 plugins

...you can better estimate the scope of work.

## Comparison with BuiltWith

| Feature | BuiltWith | UPER SEO Auditor |
|---------|-----------|------------------|
| CMS Detection | ✅ | ✅ |
| JS Frameworks | ✅ | ✅ |
| Versions | Paid | ✅ |
| SEO Integration | ❌ | ✅ |
| Offline | ❌ | ✅ |
| Price | $295+/mo | Free |

## Data Export

Detection results are included in export:

- **PDF** - Technology Stack section with icons
- **JSON** - full structure for further analysis

## Detection Limitations

Some technologies are hard to detect:

- **Server-side frameworks** - PHP, Python, Ruby (hidden behind CDN)
- **Masked stacks** - intentional technology hiding
- **Micro frontends** - mixed frameworks
- **Edge rendering** - Cloudflare Workers, Deno Deploy

## Summary

Technology detection in UPER SEO Auditor allows you to:

- **Quickly identify stack** - CMS, frameworks, libraries
- **Identify tools** - analytics, ads, chat
- **Detect versions** - security audit
- **Integrate with SEO** - everything in one panel

Instead of jumping between BuiltWith, Wappalyzer, and DevTools - you have everything in one place.

Try [UPER SEO Auditor](https://chromewebstore.google.com/detail/uper-seo-auditor/khhpbeckpphaoiemjdijhbfpjnendage) and check the technology stack of any website.

## Sources

1. **Wappalyzer - Technology Lookup**
[https://www.wappalyzer.com/](https://www.wappalyzer.com/)

2. **BuiltWith - Web Technology Profiler**
[https://builtwith.com/](https://builtwith.com/)

3. **Chrome DevTools - Network Panel**
[https://developer.chrome.com/docs/devtools/network/](https://developer.chrome.com/docs/devtools/network/)

4. **HTTP Archive - Web Almanac**
[https://almanac.httparchive.org/](https://almanac.httparchive.org/)