# Tech Stack Detector - Website Technology Lookup (CMS, Bulk) (`ventura_workalong/tech-stack-detector`) Actor

Find what software any website uses: tech stack detector and website technology lookup in bulk (CMS, ecommerce, JS frameworks, analytics, CDN, hosting, email provider) from 3,500+ fingerprints. Returns each technology with version and evidence. $0.01/site; failures free.

- **URL**: https://apify.com/ventura_workalong/tech-stack-detector.md
- **Developed by:** [Ventura WorkAlong](https://apify.com/ventura_workalong) (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 $10.00 / 1,000 website analyzeds

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 Lookup in Bulk

**Tech Stack Detector** finds out what a website is built with. Give it a list of domains or URLs and get back, for each site, the **CMS, ecommerce platform, JavaScript frameworks, analytics and marketing tools, CDN, web server, hosting and email provider** it uses. Each detection comes with a version where one is visible, a confidence score and the evidence behind it.

- **~3,600 technology fingerprints** in 100+ categories.
- **$0.01 per website analyzed.** Sites that fail aren't charged: DNS errors, timeouts, HTTP errors, bot walls and robots.txt blocks are all free.
- **Evidence for every result**, e.g. `meta generator = WordPress 6.4.2` or `MX = aspmx.l.google.com`, so you can check it.
- **Clean JSON for agents and pipelines.** One item per site, a flat `technologyNames` list for spreadsheets, and a `categories` map for quick filtering.

### How to look up a website's tech stack

1. Paste domains or URLs into **URLs**, one per line. Thousands per run are fine.
2. Optional: pick categories with **Only these categories** (e.g. `CMS`, `Ecommerce`) or raise **Min confidence**.
3. Click **Start**. Download the table as CSV/Excel, or call the Actor from the API, Make, Zapier or an AI agent (MCP).

### Use cases

- **Lead lists and sales prospecting:** find Shopify stores, WordPress sites, HubSpot users or Google Workspace companies in a list of domains.
- **Competitive and market research:** see what your competitors run, from analytics to payments.
- **AI agents (MCP):** answer "what CMS does example.com use?" in one cheap call.
- **Security and IT inventory:** you get CPE identifiers for known software and visible versions (e.g. an old jQuery).

### Input

| Field | What it does | Default |
|---|---|---|
| `urls` | Domains or URLs. A bare domain gets its homepage fetched over HTTPS, falling back to HTTP. | required |
| `minConfidence` | Hide detections below this confidence (0–100). | 50 |
| `onlyCategories` | Return only these categories, e.g. `CMS`, `Ecommerce`, `Analytics`. | all |
| `includeEvidence` | Include the matched signal for each detection. | true |
| `checkDns` | Look up MX/TXT/NS/SOA/CNAME records to find email, DNS and verified SaaS providers. | true |
| `respectRobotsTxt` | Skip pages that robots.txt disallows (skipped sites aren't charged). | true |
| `maxConcurrency` | Sites analyzed in parallel (1–20). The same host is never hit more than once a second. | 5 |
| `timeoutSecs` | Per-site timeout. | 20 |

```json
{ "urls": ["https://www.python.org", "apify.com", "example.com"], "onlyCategories": [], "minConfidence": 50 }
```

### Output example (one item per site; real output for python.org, shortened)

```json
{
  "input": "https://www.python.org",
  "finalUrl": "https://www.python.org/",
  "domain": "python.org",
  "status": "ok",
  "httpStatus": 200,
  "title": "Welcome to Python.org",
  "techCount": 13,
  "technologyNames": ["Nginx", "Varnish", "jQuery", "Modernizr", "Mailgun", "..."],
  "categories": { "Web servers": ["Nginx"], "Caching": ["Varnish"], "JavaScript libraries": ["jQuery", "jQuery UI", "Modernizr"] },
  "technologies": [
    {
      "name": "jQuery", "version": "1.8.2", "confidence": 100,
      "categories": ["JavaScript libraries"], "groups": ["Web development"],
      "website": "https://jquery.com", "cpe": "cpe:2.3:a:jquery:jquery:*:*:*:*:*:*:*:*",
      "saas": null, "oss": null, "pricing": [],
      "evidence": [{ "type": "scriptSrc", "match": "jquery" }, { "type": "scriptSrc", "match": "/1.8.2/jquery.m" }]
    }
  ],
  "dnsChecked": true,
  "error": null,
  "checkedAt": "2026-10-03T12:00:00+00:00"
}
```

`status` is `ok` (analyzed and charged), `failed` or `blocked` (both free). The **Overview** dataset view shows one row per site.

### How it works

For each site the Actor makes **one page request**, plus a robots.txt request and DNS lookups. It then checks the response headers, cookies, HTML, script URLs, inline scripts and styles, meta tags, DOM selectors, visible text and DNS records against the fingerprint database. Implied technologies are added too: WordPress implies PHP and MySQL. Plugins whose platform wasn't found are dropped. Confidence is the sum of the matched signal weights, capped at 100.

### Limits (please read)

- **No JavaScript rendering.** About 380 fingerprints can only be seen in a live browser (JavaScript variables, XHR calls), so they are never detected here. Single-page apps that render everything client-side will show fewer technologies than a browser extension would. In exchange, the Actor is fast and cheap.
- **One page per site.** Tools that only load on checkout, blog or login pages won't be seen unless you pass that URL.
- **Fingerprint data is a January 2023 snapshot.** It's the last openly licensed (MIT) release of the community fingerprint set, so very new products, or ones that have changed their markup since, may be missed. We add and fix fingerprints over time.
- **DNS TXT verification records** (e.g. `stripe-verification=`) show a service was connected to the domain at some point, not that it's in active use. Their evidence is labelled `dns`.
- **Bot protection:** sites behind challenge pages or rate limits answer with 403/429/503. Those sites come back `failed` and aren't charged. No proxies or evasion are used.
- Detection is heuristic. Treat low-confidence results (25–50) as hints.

### Responsible use

- Only public pages are requested, with an identifying user agent (`TechStackBot`).
- robots.txt is honored by default, and requests to the same host are spaced at least 1 second apart.
- Private and internal network addresses are refused.
- No personal data is collected. Output describes software, not people.

### Pricing

Pay per event: **$0.01 per website analyzed** (`site-analyzed`). Failed and blocked sites are free. Your run stops cleanly when it reaches your maximum total charge.

### Attribution

Fingerprint data comes from the Wappalyzer project, as of git commit `aff18ef` (2023-01-25), the last version released under the **MIT licence**. See `src/data/LICENSE-fingerprints.txt`. The data was merged and reformatted, and no icons were copied. The detection engine is our own code. This Actor is not affiliated with or endorsed by Wappalyzer.

### FAQ

#### What technologies can it detect?

About 3,600, in 100+ categories: CMS (WordPress, Drupal, Wix, Squarespace), ecommerce (Shopify, WooCommerce, Magento, BigCommerce), JavaScript frameworks and libraries, analytics and tag managers, advertising pixels, CDNs, web servers, hosting, payment providers, live chat, and email providers from DNS records.

#### How does it compare with BuiltWith or Wappalyzer?

It uses the same open fingerprinting approach as the Wappalyzer browser extension, from that project's last MIT-licensed data release (see Attribution). It makes one live page request per site, with no historical data and no JavaScript rendering. BuiltWith's database also includes historical and spend data that this Actor doesn't have. In exchange you pay $0.01 per site with no subscription. This Actor isn't affiliated with either company.

#### Can I find all Shopify (or WordPress) sites in my list?

Yes. Set `onlyCategories` to `["Ecommerce"]` or `["CMS"]` and filter the `technologyNames` column.

### Related Actors

- [Bulk WHOIS Domain Lookup with DNS, SSL & Security Headers](https://apify.com/ventura_workalong/domain-lookup-bundle): domain age, registrar, email provider and SSL for the same list.
- [PageSpeed Insights Bulk Checker](https://apify.com/ventura_workalong/pagespeed-insights-bulk): Core Web Vitals and Lighthouse scores.
- [Sitemap URL Extractor](https://apify.com/ventura_workalong/sitemap-url-extractor): every URL of a website.

### Support

Open an issue on the Actor page with the site URL and what you expected to see. False positives and missed technologies get fixed.

# Actor input Schema

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

Domains or URLs to analyze, e.g. `example.com` or `https://shop.example.com/`. One page per entry is fetched (the URL you give, or the homepage for a bare domain).

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

Only return technologies detected with at least this confidence. Weak single signals score 25-50; 0 returns everything.

## `onlyCategories` (type: `array`):

Optional filter by category name, e.g. `CMS`, `Ecommerce`, `Analytics`, `JavaScript frameworks`, `CDN`, `Email`. Leave empty for all categories. Filtering does not change the price.

## `includeEvidence` (type: `boolean`):

Add the matched header, cookie, meta tag, script URL, DNS record or HTML snippet behind each detection.

## `checkDns` (type: `boolean`):

Also look up MX, TXT, NS, SOA and CNAME records to detect email providers, DNS hosts and verified SaaS tools. TXT verification records show a tool was set up at some point, not that it's in active use.

## `respectRobotsTxt` (type: `boolean`):

Skip sites whose robots.txt disallows the page. Skipped sites are not charged.

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

Websites analyzed in parallel. Requests to the same host are always spaced at least 1 second apart.

## `timeoutSecs` (type: `integer`):

Give up on a site after this long.

## Actor input object example

```json
{
  "urls": [
    "https://www.python.org",
    "https://apify.com",
    "example.com"
  ],
  "minConfidence": 50,
  "includeEvidence": true,
  "checkDns": true,
  "respectRobotsTxt": true,
  "maxConcurrency": 5,
  "timeoutSecs": 20
}
```

# Actor output Schema

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

All results from this run, one item per input, in the default dataset.

# 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://www.python.org",
        "https://apify.com",
        "example.com"
    ]
};

// Run the Actor and wait for it to finish
const run = await client.actor("ventura_workalong/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://www.python.org",
        "https://apify.com",
        "example.com",
    ] }

# Run the Actor and wait for it to finish
run = client.actor("ventura_workalong/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://www.python.org",
    "https://apify.com",
    "example.com"
  ]
}' |
apify call ventura_workalong/tech-stack-detector --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,ventura_workalong/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/neOuVB7Tff1NFU3Eb/builds/X7jTTdA5Rx2m9IEor/openapi.json