# Tech Stack Detector: Website Technology Checker (`phaux/tech-stack-detector`) Actor

Detect what a website is built with: CMS, e-commerce platform, JS frameworks, analytics, CDN, hosting and 7,600+ technologies (open fingerprints). Use to profile sites or lead lists. Input: urls. Output per URL: technologies with name, categories, version, confidence, evidence. Obeys robots.txt.

- **URL**: https://apify.com/phaux/tech-stack-detector.md
- **Developed by:** [Phaux](https://apify.com/phaux) (community)
- **Categories:** Lead generation, Developer tools, SEO tools
- **Stats:** 2 total users, 1 monthly users, 100.0% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet

## Pricing

from $1.50 / 1,000 results

This Actor is paid per event. You are not charged for the Apify platform usage, but only a fixed price for specific events.

Learn more: https://docs.apify.com/actors/running/actors-in-store.md#pay-per-event

## What's an Apify Actor?

An Actor is a serverless cloud program that runs on the Apify platform. It has two run modes.
In Batch mode, an Actor accepts a well-defined JSON input, performs an action which can take anything from a few seconds to a few hours,
and optionally produces a well-defined JSON output, datasets with results, or files in key-value store.
In Standby mode, an Actor provides a web server which can be used as a website, API, or an MCP server.

Apify vocabulary and the platform model are defined once, in the agent quickstart at https://apify.com/agents.md.

## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.

Do not guess an integration path. Every one of them is in the agent quickstart at https://apify.com/agents.md: the Apify MCP server, Agent Skills with the Apify CLI, the JavaScript and Python clients, the REST API, and the account-free path for an agent with no human to sign in. It also carries the rule on stating cost before the first paid run.

For examples already wired to this Actor's own input schema, see the [API](#api) section below.

Each client library has reference documentation the quickstart does not restate: [JavaScript/TypeScript](https://docs.apify.com/api/client/js/docs.md) (`npm install apify-client`) and [Python](https://docs.apify.com/api/client/python/docs.md) (`pip install apify-client`).

# README

## Tech Stack Detector: Website Technology Checker

A **website technology detector**: give it a list of URLs and see the **tech stack** each site runs, for lead lists, market research or keeping an inventory of your own sites.

Find out what any public website is built with: **CMS, e-commerce platform, JavaScript frameworks, analytics and tag managers, CDN, hosting, web server, marketing tools** and more. Each result lists the detected technologies with **version** (where the site exposes it), **confidence** and the **evidence** behind each detection. More than 7,600 technologies are covered.

### Quick start for AI agents and API users

- **What it does:** Detect what a website is built with: CMS, e-commerce platform, JS frameworks, analytics, CDN, hosting and 7,600+ technologies (open fingerprints).
- **When to use it:** To profile sites or lead lists.
- **Example input** (the form's prefill; it finishes in under a minute):

```json
{
  "urls": [
    "https://wordpress.org/news/",
    "https://www.shopify.com/",
    "https://apify.com/"
  ]
}
```

- **Example output:** one real dataset row from run `T4LQ0nYx5csIqGTle` (2026-10-23), with long fields shortened and empty fields left out. Fields not shown are listed in the output table below.

```json
{
  "url": "https://wordpress.org/news/",
  "finalUrl": "https://wordpress.org/news/",
  "domain": "wordpress.org",
  "httpStatus": 200,
  "title": "WordPress News – The latest news about WordPress and the WordPress community",
  "technologyCount": 12,
  "technologies": [
    {
      "name": "Google Font API",
      "version": null,
      "confidence": 100,
      "categories": [
        "Font scripts"
      ],
      "website": "https://fonts.google.com/",
      "cpe": null,
      "detectedBy": [
        "dom"
      ]
    },
    {
      "name": "Google Tag Manager",
      "version": null,
      "confidence": 100,
      "categories": [
        "Tag managers"
      ],
      "website": "https://www.google.com/tagmanager",
      "cpe": null,
      "detectedBy": [
        "html"
      ]
    },
    "..."
  ],
  "categories": [
    "Blogs",
    "CMS",
    "..."
  ],
  "server": "nginx",
  "htmlTruncated": false,
  "detectedAt": "2026-10-23T13:11:01Z"
}
```

- **Cost (pay per event, Free-plan prices):** Actor Start $0.002; result $0.0015. Failed items are not charged.
- **From an AI agent:** with the Apify MCP server, call `call-actor` with actor `phaux/tech-stack-detector`, or load it as its own tool with `https://mcp.apify.com?tools=phaux/tech-stack-detector`. Read results with `get-dataset-items`.

### What does Tech Stack Detector do?

- Fetches each URL you give it with a plain HTTP request (no browser) and analyzes the response headers, cookies, URL, `<meta>` tags, script URLs, inline scripts, HTML, visible text and DOM selectors.
- Matches them against the open Wappalyzer-compatible fingerprint database [enthec/webappanalyzer](https://github.com/enthec/webappanalyzer) (GPL-3.0), pinned to a reviewed commit, and applies its `implies`, `requires` and `excludes` rules (WordPress implies PHP and MySQL, for example).
- Returns **one dataset item per analyzed URL**.

### Why use it?

- **Live detection:** each URL is fetched at run time, not looked up in an old index.
- **Fast and cheap:** plain HTTP, no browser.
- **Pay only for analyzed URLs:** pages that fail, are blocked, or are disallowed by robots.txt cost nothing.
- **Explainable:** `detectedBy` shows which signals matched, and `minConfidence` hides weak guesses.

Use cases: lead generation and lead enrichment by technology (for example, "stores on Shopify"), competitive research, sales prospecting lists, SEO and security audits, and tracking technology changes over time.

### How to use it

1. Add website URLs or bare domains to `urls` (`https://` is added if missing).
2. Optionally set `minConfidence` or keep only some `categories` (for example `["CMS", "Ecommerce", "Analytics"]`).
3. Run the Actor and open the **Tech stacks** dataset view, or download JSON, CSV or Excel.

### Input

```json
{
  "urls": ["https://wordpress.org/news/", "shopify.com", "https://apify.com/"],
  "minConfidence": 50,
  "categories": [],
  "includeDetectedBy": true,
  "maxConcurrency": 5
}
```

| Field | Type | Default | Description |
|---|---|---|---|
| `urls` | array | required | Public web pages to analyze, e.g. https://www.example.com or example.com (https:// is added). One result per URL. Max 5,000 per run. |
| `minConfidence` | integer | `50` | Only report technologies detected with at least this confidence (0-100). |
| `categories` | array | — | Optional. Keep only technologies in these categories, e.g. 'CMS', 'Analytics', 'Ecommerce', 'JavaScript frameworks', 'CDN'. Empty = all. |
| `includeDetectedBy` | boolean | `true` | Add which signals (headers, cookies, scriptSrc, html, meta, dom...) matched each technology. |
| `maxConcurrency` | integer | `5` | How many URLs to process at once (1-10). Requests to the same host are always sequential, at least 1 s apart (or the site's robots.txt Crawl-delay). |
| `requestTimeoutSecs` | integer | `20` | How long to wait for each page (and its robots.txt) to respond, in seconds. Slow pages are reported in FAILED_URLS and not charged. |

### Output example

One dataset item per analyzed URL:

```json
{
  "url": "https://wordpress.org/news/",
  "finalUrl": "https://wordpress.org/news/",
  "domain": "wordpress.org",
  "httpStatus": 200,
  "title": "WordPress News – The latest news about WordPress and the WordPress community",
  "technologyCount": 12,
  "technologies": [
    {"name": "WordPress", "version": "7.2", "confidence": 100, "categories": ["CMS", "Blogs"],
     "website": "https://wordpress.org", "cpe": "cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*",
     "detectedBy": ["html", "meta", "scriptSrc"]},
    {"name": "PHP", "version": null, "confidence": 100, "categories": ["Programming languages"], "detectedBy": ["implied by WordPress"]}
  ],
  "categories": ["Blogs", "CMS", "Databases", "Font scripts", "Programming languages", "Tag managers", "Web servers"],
  "server": "nginx",
  "redirects": [],
  "htmlTruncated": false,
  "fingerprints": "enthec/webappanalyzer@d91f7e5",
  "detectedAt": "2026-10-20T13:30:00Z"
}
```

### Output fields

| Field | Type | Description |
|---|---|---|
| `url` | string | URL as given (normalized). |
| `finalUrl` | string or null | URL after redirects. |
| `domain` | string or null | Host name of the final URL. |
| `httpStatus` | integer or null | HTTP status of the final response. |
| `title` | string or null | Page title (emails and phone numbers removed). |
| `technologyCount` | integer | Number of technologies reported. |
| `technologies` | array | Detected technologies: name, version, confidence, categories, website, cpe, detectedBy. |
| `categories` | array | Distinct categories of the detected technologies. |
| `server` | string or null | Server response header. |
| `redirects` | array | Redirect chain before the final URL. |
| `htmlTruncated` | boolean | True if the page was larger than 3 MB and only the first 3 MB was analyzed. |
| `fingerprints` | string | Fingerprint database and commit used. |
| `detectedAt` | string | When the page was analyzed (ISO 8601, UTC). |

Each entry in `technologies` has `name`, `version` (or null), `confidence` (0–100), `categories`, `website`, `cpe` (when known) and, if `includeDetectedBy` is on, `detectedBy`.

The run also saves `FAILED_URLS` (every URL that wasn't analyzed, with a reason code: `robots_disallowed`, `http_error`, `rate_limited`, `network_error`, `dns_error`, `blocked_host`, `invalid_url`, `not_html`) and `RUN_STATS` in the key-value store.

### How much does it cost?

Pay per event. Apify platform usage is included.

| Event | Price |
|---|---|
| Actor start | $0.002 per run (one event per GB of memory; the default 512 MB counts as one) |
| Analyzed URL (one dataset item) | $0.0015 ($1.50 per 1,000 URLs) |

Example: 100 URLs in one run cost $0.002 + $0.15 = $0.152. Failed, blocked and disallowed URLs are **not charged**.

### Use with AI agents, MCP and the API

- **MCP:** add `https://mcp.apify.com?tools=phaux/tech-stack-detector` to any MCP client and ask, for example, "what CMS does example.com use?".
- **API:** `POST https://api.apify.com/v2/acts/phaux~tech-stack-detector/run-sync-get-dataset-items` with `{"urls": ["example.com"]}` returns the result directly.
- Output field names and types are documented in the dataset schema.

### Data source and compliance

- The Actor reads only the **public page you give it**, plus that site's `/robots.txt`. It never logs in, never sends cookies or forms, and needs no API key.
- It **obeys robots.txt** (RFC 9309) for its user agent `PhauxTechStackBot` and honours `Crawl-delay`. Disallowed URLs are skipped and reported as `robots_disallowed` (not charged).
- It identifies itself honestly (`Mozilla/5.0 (compatible; PhauxTechStackBot/0.1; +https://apify.com/phaux/tech-stack-detector)`), uses **no proxies and no IP rotation**, and does nothing to get around bot protection. After an HTTP 429 it doesn't contact that site again during the run.
- Polite pacing: one request at a time per host, at least 1 second apart.
- Only `http(s)` URLs on public IP addresses are fetched, and redirects are checked at every hop.
- No personal data is collected. Email addresses and phone numbers are removed from page titles.

### Limits

- Signals that need JavaScript execution or DNS lookups (`js`, `xhr`, `dns` fingerprints) aren't used, so some client-side-only tools can be missed.
- Only the first 3 MB of HTML is analyzed (`htmlTruncated` tells you when that happened).
- Up to 5,000 URLs per run. Sites that refuse automated clients (HTTP 403) aren't analyzed and aren't charged.
- License: the fingerprints are © their contributors under GPL-3.0 and are used unmodified. The detection code is independent.

### FAQ

- **Why did a site fail with HTTP 403?** Some sites refuse automated clients. The Actor respects that and doesn't try to evade it, and you aren't charged.
- **Can it detect a technology behind a login?** No. Only public pages are analyzed.
- **Something isn't working?** Open an issue on the Issues tab with the run ID.

# Actor input Schema

## `urls` (type: `array`):

Public web pages to analyze, e.g. https://www.example.com or example.com (https:// is added). One result per URL. Max 5,000 per run.

## `minConfidence` (type: `integer`):

Only report technologies detected with at least this confidence (0-100). Default: 50.

## `categories` (type: `array`):

Optional. Keep only technologies in these categories, e.g. 'CMS', 'Analytics', 'Ecommerce', 'JavaScript frameworks', 'CDN'. Empty = all.

## `includeDetectedBy` (type: `boolean`):

Add which signals (headers, cookies, scriptSrc, html, meta, dom...) matched each technology. Default: true.

## `maxConcurrency` (type: `integer`):

How many URLs to process at once (1-10). Requests to the same host are always sequential, at least 1 s apart (or the site's robots.txt Crawl-delay). Default: 5.

## `requestTimeoutSecs` (type: `integer`):

How long to wait for each page (and its robots.txt) to respond, in seconds. Slow pages are reported in FAILED_URLS and not charged. Default: 20.

## Actor input object example

```json
{
  "urls": [
    "https://wordpress.org/news/",
    "https://www.shopify.com/",
    "https://apify.com/"
  ],
  "minConfidence": 50,
  "includeDetectedBy": true,
  "maxConcurrency": 5,
  "requestTimeoutSecs": 20
}
```

# Actor output Schema

## `results` (type: `string`):

All analyzed URLs (default dataset, overview view).

## `failedUrls` (type: `string`):

URLs that could not be analyzed, with the reason (robots.txt, HTTP error, 429, timeout...).

## `runStats` (type: `string`):

RUN_STATS record.

# API

You can run this Actor programmatically using our API. Below are code examples in JavaScript, Python, and CLI, as well as the OpenAPI specification and MCP server setup.

## JavaScript example

```javascript
import { ApifyClient } from 'apify-client';

// Initialize the ApifyClient with your Apify API token
// Replace the '<YOUR_API_TOKEN>' with your token
const client = new ApifyClient({
    token: '<YOUR_API_TOKEN>',
});

// Prepare Actor input
const input = {
    "urls": [
        "https://wordpress.org/news/",
        "https://www.shopify.com/",
        "https://apify.com/"
    ]
};

// Run the Actor and wait for it to finish
const run = await client.actor("phaux/tech-stack-detector").call(input);

// Fetch and print Actor results from the run's dataset (if any)
console.log('Results from dataset');
console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
items.forEach((item) => {
    console.dir(item);
});

// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

```

## Python example

```python
from apify_client import ApifyClient

# Initialize the ApifyClient with your Apify API token
# Replace '<YOUR_API_TOKEN>' with your token.
client = ApifyClient("<YOUR_API_TOKEN>")

# Prepare the Actor input
run_input = { "urls": [
        "https://wordpress.org/news/",
        "https://www.shopify.com/",
        "https://apify.com/",
    ] }

# Run the Actor and wait for it to finish
run = client.actor("phaux/tech-stack-detector").call(run_input=run_input)

# Fetch and print Actor results from the run's dataset (if there are any)
print(f"💾 Check your data here: https://console.apify.com/storage/datasets/{run.default_dataset_id}")
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item)

# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start

```

## CLI example

```bash
echo '{
  "urls": [
    "https://wordpress.org/news/",
    "https://www.shopify.com/",
    "https://apify.com/"
  ]
}' |
apify call phaux/tech-stack-detector --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,phaux/tech-stack-detector"
        }
    }
}
```

The hosted server signs you in with OAuth on first connect, so no API token belongs in this config. Clients without OAuth support can send an `Authorization: Bearer <APIFY_API_TOKEN>` header instead, using a token from API & Integrations in Apify Console (https://console.apify.com/settings/integrations).

## OpenAPI specification

Download the OpenAPI definition: https://api.apify.com/v2/actors/rH3fl60XkmVdfp6I8/builds/0jGtAA5svg7V3ez23/openapi.json