# Tech Stack Detector & Website Technology Lookup in Bulk (`fecklesspleb/tech-stack-detector`) Actor

Tech stack detector for any list of websites: find the CMS, ecommerce platform, JavaScript framework, analytics, ad pixels, marketing tools, CDN and hosting each site uses. 136 technologies in 38 categories, with version and evidence. CSV or JSON export. Sites that fail are free.

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

## Pricing

Pay per event

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, $2 per 1,000 sites

Tech Stack Detector tells you what a website is built with. Give it a list of websites and get the technologies each one uses: CMS, ecommerce platform, JavaScript framework, analytics, ad pixels, marketing automation, live chat, cookie consent, CDN, hosting, web server and more. Every detection comes with its category, the version when the site exposes it, and the evidence it was found from (a response header, meta tag, script, link, cookie name or HTML pattern).

It detects 136 technologies in 38 categories, using fingerprint rules written for this Actor. One fast HTTP page request per website (plus its robots.txt). No browser, no proxy, no login. It obeys robots.txt.

**At a glance:** $0.002 per website that returns a page ($2.00 per 1,000); rows for websites that could not be read are free. Pay per result with no subscription, set a maximum cost per run, export to JSON, CSV, Excel or HTML, or call it from the Apify API, n8n, Make or Zapier.

### Who it's for

- **Sales and lead generation teams** building lists of companies that use (or do not use) a platform, such as WooCommerce stores or WordPress sites.
- **Market researchers** measuring technology adoption across a list of domains.
- **Agencies and consultants** checking a prospect's CMS, hosting and analytics before a pitch, redesign or migration.
- **CRM enrichment:** add the tech stack to company records through n8n, Make or Zapier.

### What it detects

| Category | Technologies |
|---|---|
| CMS | Drupal, Ghost, HubSpot CMS, Joomla, MediaWiki, WordPress |
| Headless CMS | Contentful, Sanity, Strapi |
| Site builder | Framer, Squarespace, Webflow, Wix |
| Static site generator | Astro, Docusaurus, Gatsby, Hugo, Jekyll |
| Ecommerce | BigCommerce, Magento, PrestaShop, Salesforce Commerce Cloud, WooCommerce |
| Payments | Klarna, PayPal, Stripe |
| JavaScript framework | Angular, AngularJS, Ember.js, Next.js, Nuxt, React, Remix, Svelte, SvelteKit, Vue.js |
| JavaScript library | Alpine.js, GSAP, htmx, jQuery, Lodash, Three.js |
| UI framework | Bootstrap, Tailwind CSS |
| Analytics | Adobe Analytics, Amplitude, Cloudflare Web Analytics, Fathom, Google Analytics, Heap, Hotjar, Matomo, Microsoft Clarity, Mixpanel, Plausible, PostHog, Segment, Vercel Analytics |
| Tag manager | Google Tag Manager |
| Advertising | Google AdSense, Google Ads, LinkedIn Insight Tag, Meta Pixel, TikTok Pixel, X (Twitter) Pixel |
| A/B testing | Optimizely, VWO |
| Marketing automation | HubSpot, Marketo, Pardot |
| Email marketing | Klaviyo, Mailchimp |
| Live chat | Crisp, Drift, Freshchat, Intercom, Tawk.to |
| Customer support | Zendesk |
| Cookie consent | Cookiebot, OneTrust, Osano |
| Forms and scheduling | Typeform, Calendly |
| Search | Algolia |
| Video | Vimeo, Wistia, YouTube embed |
| Font | Adobe Fonts, Font Awesome, Google Fonts |
| Blogging and docs | Medium, Substack, GitBook, Mintlify |
| CDN and cache | Akamai, Amazon CloudFront, Cloudflare, Fastly, Varnish |
| Hosting | Amazon Web Services, Fly.io, GitHub Pages, Google Cloud, Heroku, Kinsta, Microsoft Azure, Netlify, Render, Vercel, WP Engine |
| Web server | Apache, Caddy, LiteSpeed, Microsoft IIS, Nginx |
| Web framework | Django, Express, Laravel, Microsoft ASP.NET, Ruby on Rails |
| Programming language and database | Java, Node.js, PHP, MySQL |
| Monitoring | Datadog RUM, New Relic, Sentry |
| Security | Cloudflare Turnstile, hCaptcha, HSTS, reCAPTCHA |
| Other | HTTP/3, PWA manifest, Open Graph, Schema.org JSON-LD |

Some technologies are implied by others. For example, Next.js implies React and Node.js, and WordPress implies PHP and MySQL. Implied detections say so in their evidence (`"implied by Next.js"`).

### How to use it

1. Open the Actor in Apify Console and click **Try for free**.
2. Paste your websites into **Websites**, one per line. Bare domains like `nextjs.org` work; `https://` is added for you. Duplicates are removed.
3. Optional: turn on **Include response headers** to also get the response headers, or turn off **Include failed URLs** to skip sites that could not be read.
4. Click **Start** and export the dataset to CSV or Excel. Filter by `technologyNames` or `categories` to build your list.

### Input

| Field | Type | Default | Description |
|---|---|---|---|
| `urls` | array (required) | `["https://www.python.org/"]` | Websites to check. Each one is fetched once. |
| `includeHeaders` | boolean | false | Add the HTTP response headers to each row (cookies are left out). |
| `includeFailedUrls` | boolean | true | Also save rows for websites that could not be read (DNS errors, timeouts, HTTP 400 and above, robots.txt). These rows are free. Turn off to skip them. |
| `maxConcurrency` | integer, 1 to 30 | 10 | How many websites to check at the same time. |
| `maxResults` | integer | 0 | Stop after this many rows. 0 means no limit. |

#### Example input

```json
{
  "urls": [
    {"url": "https://www.python.org"},
    {"url": "nextjs.org"}
  ],
  "includeHeaders": false,
  "includeFailedUrls": false
}
```

### Output

One row per website. This is a real row from a test run:

```json
{
  "url": "https://nextjs.org",
  "finalUrl": "https://nextjs.org",
  "statusCode": 200,
  "technologies": [
    {"name": "Vercel", "category": "Hosting", "version": null, "evidence": ["header:server", "header:x-vercel-id"]},
    {"name": "Next.js", "category": "JavaScript framework", "version": null, "evidence": ["html"]},
    {"name": "React", "category": "JavaScript framework", "version": null, "evidence": ["implied by Next.js"]},
    {"name": "Node.js", "category": "Programming language", "version": null, "evidence": ["implied by Next.js"]},
    {"name": "Open Graph", "category": "SEO", "version": null, "evidence": ["meta:og:title"]},
    {"name": "Schema.org JSON-LD", "category": "SEO", "version": null, "evidence": ["html"]},
    {"name": "HSTS", "category": "Security", "version": null, "evidence": ["header:strict-transport-security"]}
  ],
  "technologyNames": ["Vercel", "Next.js", "React", "Node.js", "Open Graph", "Schema.org JSON-LD", "HSTS"],
  "technologyCount": 7,
  "categories": {
    "Hosting": ["Vercel"],
    "JavaScript framework": ["Next.js", "React"],
    "Programming language": ["Node.js"],
    "SEO": ["Open Graph", "Schema.org JSON-LD"],
    "Security": ["HSTS"]
  },
  "error": null,
  "checkedAt": "2026-10-30T01:31:18.993408+00:00"
}
```

Versions appear when the site exposes them, for example `{"name": "jQuery", "version": "1.8.2"}` on python.org in the same test run.

| Field | Description |
|---|---|
| `url`, `finalUrl` | The URL you gave and the URL after redirects |
| `statusCode` | HTTP status of the response |
| `technologies` | Each detection with `name`, `category`, `version` (or `null`) and `evidence` |
| `technologyNames` | Just the names, easy to filter in a spreadsheet |
| `technologyCount` | Number of technologies detected |
| `categories` | Technology names grouped by category |
| `headers` | Response headers, only with **Include response headers** |
| `error` | `null` on success; otherwise for example `HTTP 403`, `DNS or connection error`, or `not fetched: robots.txt disallows it` |
| `checkedAt` | When the website was fetched (UTC) |

The `RUN_SUMMARY` record in the key-value store has the number of URLs, how many succeeded and failed, rows saved, and whether the run stopped at your cost limit.

### Pricing

This Actor uses pay-per-event pricing. You pay per website, not for compute time.

| Event | Price |
|---|---|
| Website checked (one row) | $0.002 |
| Actor start (charged by Apify, once per GB of run memory; 1 event at the default 1 GB) | $0.00005 |

Examples:

- 100 websites: 100 × $0.002 + $0.00005 = **about $0.20**.
- 1,000 websites: **about $2.00**.
- 10,000 websites: **about $20.00**.

Rows for websites that could not be read (HTTP 400 and above, DNS or connection errors, timeouts, robots.txt) are free. You pay only for websites that returned a page with status below 400. **Include failed URLs** only decides whether those free rows are saved; they still count toward **Max results**.

**Set a maximum cost per run.** In Apify Console set **Maximum cost per run**, or pass `maxTotalChargeUsd` through the API. The Actor stops cleanly when the limit is reached and the status message says so.

### Integrations and API

The Actor ID is `fecklesspleb/tech-stack-detector` (in API URLs: `fecklesspleb~tech-stack-detector`).

- **n8n:** use the Apify node, choose **Run an Actor** with this Actor ID, then read the dataset items and write the stack to your CRM or a sheet.
- **Make:** use the Apify module **Run an Actor**, then **Get Dataset Items**.
- **Zapier:** use the Apify app with **Run Actor**, then a dataset items step, for example when a new lead is added.
- **Schedules:** create an Apify schedule to re-check a list of domains every month, and a webhook to get notified when a run finishes.
- **AI agents:** call it through the Apify API, the Apify clients, or Apify's MCP server.

#### Run it with curl

```bash
curl -X POST "https://api.apify.com/v2/acts/fecklesspleb~tech-stack-detector/run-sync-get-dataset-items?token=YOUR_APIFY_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"urls": [{"url": "https://www.python.org"}, {"url": "nextjs.org"}], "includeFailedUrls": false}'
```

#### Python

```python
from apify_client import ApifyClient

client = ApifyClient("YOUR_APIFY_TOKEN")
run = client.actor("fecklesspleb/tech-stack-detector").call(
    run_input={"urls": [{"url": "https://www.python.org"}, {"url": "nextjs.org"}]},
    max_total_charge_usd=1,
)
for row in client.dataset(run["defaultDatasetId"]).iterate_items():
    print(row["url"], row.get("technologyNames"))
```

#### JavaScript

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

const client = new ApifyClient({ token: 'YOUR_APIFY_TOKEN' });
const run = await client.actor('fecklesspleb/tech-stack-detector').call({
    urls: [{ url: 'https://www.python.org' }, { url: 'nextjs.org' }],
});
const { items } = await client.dataset(run.defaultDatasetId).listItems();
console.log(items.filter((r) => r.technologyNames?.includes('WordPress')).map((r) => r.url));
```

### Limits

- It checks the page at the URL you give (usually the home page), not the whole site. A tool used only on other pages is not seen.
- It reads the HTML and headers the server sends, without running JavaScript. Tools loaded only later by a tag manager may not appear.
- Sites behind bot protection may return an error row or fewer detections.
- On the Apify platform, sites whose address is private, loopback or link-local (also after a redirect) are not fetched. They get a free error row: `not fetched: private, loopback and link-local addresses are not allowed`.
- Detection covers the 136 technologies in its fingerprint rules, most of them listed above. Anything else is not reported.

### Common searches this Actor answers

- what is this website built with
- tech stack lookup for a list of domains
- website technology lookup in bulk
- what CMS is this site using
- find WordPress or WooCommerce sites from a domain list
- detect analytics and ad pixels on a website
- website technology detector API

### FAQ

**How do I find out what a website is built with?**
Add the website to **Websites** and run the Actor. You get each detected technology with its category, version when visible, and the evidence it was found from.

**Can I check thousands of websites at once?**
Yes. Paste the whole list. Each website is fetched once, up to 30 at a time, at $0.002 per website that returns a page.

**Is this a Wappalyzer or BuiltWith alternative?**
It does the same kind of job: it detects technologies from a website's public HTML and response headers. It is not affiliated with Wappalyzer or BuiltWith and does not use their data. It uses its own fingerprint rules for 136 technologies and checks websites live; it has no historical data.

**How do I find all WordPress sites (or WooCommerce stores) in a list of domains?**
Run the list and filter the dataset where `technologyNames` contains `WordPress` (or `WooCommerce`). The `categories` field also groups names, for example `Ecommerce` or `CMS`.

**Why is a technology I know the site uses missing?**
It may be loaded only by JavaScript after the page opens, used on a different page, or not among the 136 technologies the Actor knows.

**Does it show versions?**
When the site exposes a version, for example in a generator meta tag or a script file name, it is in the `version` field. Otherwise `version` is `null`.

**Do I pay for websites that fail?**
No. Rows for websites that could not be read are free: HTTP 400 and above, DNS or connection errors, timeouts, and websites robots.txt disallows, directly or through a redirect. With **Include failed URLs** on (the default) you get these free error rows; turn it off to skip them.

**Is it legal?**
The Actor reads public pages the same way a browser does, obeys robots.txt, never logs in, and does not store cookies or personal data. You are responsible for how you use the results.

### Related Actors

- [Website Metadata Extractor](https://apify.com/fecklesspleb/website-metadata-extractor): titles, meta tags, Open Graph and JSON-LD for the same list of URLs.
- [Website SEO Audit](https://apify.com/fecklesspleb/website-seo-audit): crawl a site and score every page for on-page SEO.
- [Broken Link Checker](https://apify.com/fecklesspleb/broken-link-checker): find 404s and dead links on a site.
- [ATS Jobs Scraper](https://apify.com/fecklesspleb/ats-jobs-scraper): get open jobs for a list of companies from their Greenhouse, Lever, Ashby, Workable, Recruitee and Workday career boards, a hiring signal to pair with tech stack data.

# Changelog

This Actor's version history is a separate document: https://apify.com/fecklesspleb/tech-stack-detector/changelog.md

# Actor input Schema

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

Website URLs or bare domains to analyze. Plain URLs or {"url": ...} objects both work.

## `includeHeaders` (type: `boolean`):

Add the HTTP response headers (without cookies) to each row.

## `includeFailedUrls` (type: `boolean`):

Add a row with the error for websites that fail (HTTP 400 or higher, DNS or connection errors, timeouts, robots.txt blocks). These rows are free. Turn off to skip them.

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

Websites fetched in parallel.

## `maxResults` (type: `integer`):

Cap per run. 0 means no cap.

## Actor input object example

```json
{
  "urls": [
    "https://www.python.org/"
  ],
  "includeHeaders": false,
  "includeFailedUrls": true,
  "maxConcurrency": 10,
  "maxResults": 0
}
```

# Actor output Schema

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

No description

## `summary` (type: `string`):

No description

# 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/"
    ]
};

// Run the Actor and wait for it to finish
const run = await client.actor("fecklesspleb/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/"] }

# Run the Actor and wait for it to finish
run = client.actor("fecklesspleb/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/"
  ]
}' |
apify call fecklesspleb/tech-stack-detector --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,fecklesspleb/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/4auf3Vp5ps22w0Wnl/builds/xg7C25w58eWuEHnoN/openapi.json