# Tech Stack Detector - Wappalyzer & BuiltWith Alternative (`plainsight/tech-stack-detector`) Actor

Find the technologies behind any website: CMS, ecommerce platform, analytics, frameworks, CDN, payment and marketing tools, plus the SaaS tools a company verifies in DNS (HubSpot, Atlassian, Salesforce, OpenAI...). 7,600+ fingerprints, bulk input, $4 per 1,000 sites.

- **URL**: https://apify.com/plainsight/tech-stack-detector.md
- **Developed by:** [kaleb ashton](https://apify.com/plainsight) (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 $4.00 / 1,000 website analyseds

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: find the technologies behind any website

Paste a list of domains and get back each website's **CMS, ecommerce platform, analytics, advertising pixels, frameworks, CDN, hosting, payment providers, marketing tools and more**, plus something most tech lookups can't show you: the **SaaS tools the company uses internally** (HubSpot, Salesforce, Atlassian, Microsoft 365, Zoom, Figma, OpenAI...), revealed by public DNS verification records.

- 🔍 **7,600+ technology fingerprints**, refreshed from the open-source database on every run
- 🏢 **Company tools from DNS**: internal software you can't see on the website itself
- 📄 **Bulk input**: domains, URLs or email addresses, thousands per run
- 💸 **$4 per 1,000 websites**. Unreachable, blocked and error pages are **free**
- 🔑 No API key, no subscription, no browser extension

### What can you use it for?

| You are... | Use it to... |
|---|---|
| **Sales / SDR team** | Build lists of companies that use (or don't use) a tool you integrate with or replace, e.g. "Shopify stores using Klaviyo" or "companies on HubSpot". |
| **Agency** | Find WordPress, Wix or Squarespace sites to pitch redesigns, migrations or maintenance plans. |
| **SaaS founder** | Size your market, and track competitor adoption across thousands of sites. |
| **Investor / analyst** | Map technology adoption in a sector or portfolio. |
| **Security team** | Inventory your own domains and spot outdated software versions (CPE identifiers included). |
| **AI agent builder** | Give your agent a fast, cheap "what is this site built with?" tool via API or MCP. |

### What data do you get?

For every website:

- **Quick answers**: `cms`, `ecommercePlatform`, `pageBuilder`, `webServer`, `cdn`, `paas`
- **Stacks by purpose**: `analytics`, `tagManagers`, `advertising`, `marketingAutomation`, `crm`, `liveChat`, `paymentProcessors`, `buyNowPayLater`, `abTesting`, `cookieConsent`, `reviews`, `emailTools`, `aiTools`, `shopifyApps`, `wordpressPlugins`, `jsFrameworks`, `webFrameworks`, `programmingLanguages`, `security`
- **Full technology list** with category, version (when exposed), confidence, website, icon, pricing model, CPE and the evidence behind each detection
- **Company tools from DNS** (`companyToolsFromDns`): e.g. Atlassian Cloud, Microsoft 365, Google Workspace, HubSpot, Salesforce, Zoom, Figma, Miro, DocuSign, OpenAI, Anthropic, Cursor, Jamf, HackerOne
- `techNames` and `companyToolNames` as comma-separated text, so CSV / Excel / Google Sheets exports stay readable

#### Sample output (trimmed)

```json
{
  "domain": "basecamp.com",
  "url": "https://basecamp.com/",
  "cdn": "Cloudflare",
  "jsFrameworks": ["Stimulus"],
  "marketingAutomation": ["MailChimp"],
  "techNames": "Bootstrap, Stimulus, Cloudflare, MailChimp, Priority Hints, Open Graph",
  "companyToolNames": "Atlassian Cloud, Microsoft 365, Cloudflare DNS, Zoom",
  "technologies": [
    {
      "name": "Cloudflare",
      "categories": ["CDN"],
      "confidence": 100,
      "version": null,
      "website": "https://www.cloudflare.com",
      "evidence": ["header:server", "header:cf-ray", "dns:NS"]
    }
  ]
}
```

### How to use it

1. Paste your domains into **Websites** (one per line; `https://`, `www.` and paths are fine, and emails are converted to their domain).
2. Click **Start**.
3. Download the results as **CSV, Excel, JSON or HTML**, or send them to Google Sheets, Make, Zapier, n8n, Clay or your CRM via the Apify integrations.

#### Run it from code

```bash
curl -X POST "https://api.apify.com/v2/acts/plainsight~tech-stack-detector/run-sync-get-dataset-items?token=YOUR_API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"domains": ["stripe.com", "notion.so", "allbirds.com"]}'
```

```python
from apify_client import ApifyClient

client = ApifyClient("YOUR_API_TOKEN")
run = client.actor("plainsight/tech-stack-detector").call(run_input={"domains": ["stripe.com", "notion.so"]})
for site in client.dataset(run["defaultDatasetId"]).iterate_items():
    print(site["domain"], site["cms"], site["techNames"])
```

**AI agents**: this Actor works as a tool through the [Apify MCP server](https://mcp.apify.com) (Claude, Cursor, VS Code and other MCP clients), and agents can pay per call without an Apify account via x402.

### Pricing

You pay **$0.004 per website successfully analysed** ($4 per 1,000). You are **not charged** for domains that don't resolve, time out, return an error page, or block automated visitors. Those rows are still in your results so you can see what happened.

Apify's free plan includes monthly platform credit, enough to analyse roughly a thousand websites a month for free.

**Try it free:** start a run with an empty input and it analyses 3 sample websites at no charge, so you can see the exact output format first.

### How does detection work?

For each website the Actor loads the homepage (following redirects), `robots.txt` and the domain's DNS records (TXT, MX, NS, SOA, CNAME), then matches them against the [webappanalyzer](https://github.com/enthec/webappanalyzer) fingerprint database, the actively maintained open-source continuation of the Wappalyzer fingerprints (GPL-3.0). It checks HTML, script URLs, inline scripts, HTTP headers, cookies, meta tags, DOM selectors, robots.txt and DNS records, and resolves implied technologies (e.g. WooCommerce → WordPress → PHP).

The database is downloaded fresh at the start of every run, so newly added technologies are picked up automatically.

**Limitations (honest ones):** detection is based on what a server sends. The page's JavaScript isn't executed in a browser, so technologies that can only be seen at runtime (a small share of fingerprints) may be missed, and single-page apps that render everything client-side can show fewer results. Sites behind aggressive bot protection may return a challenge page; those are free.

### FAQ

**How is this different from BuiltWith or Wappalyzer?**
There's no subscription and no per-seat pricing. You pay per website, and failed lookups are free. You also get DNS-level company tools, which website-only scanners miss.

**Is it legal?**
It reads publicly available information only: the public homepage, robots.txt and public DNS records, the same data any browser or DNS resolver sees. You are responsible for how you use the results (e.g. GDPR/CAN-SPAM rules for outreach).

**How fast is it?**
It analyses 25 websites in parallel by default (adjustable up to 100). A list of 1,000 websites typically finishes in 5-10 minutes; runs can go for up to 6 hours by default, so lists of tens of thousands are fine.

**Can I schedule it?**
Yes. Use Apify Schedules to re-check a list daily or weekly and get notified when a company adopts a new tool.

### Related tools by the same developer

- [Company Enrichment](https://apify.com/plainsight/company-enrichment): one call per domain returns profile, contacts, socials, tech stack, email provider, domain age and hosting.
- [Website Contact Extractor](https://apify.com/plainsight/website-contact-extractor): emails, phones and social profiles from company websites.
- [Email Provider & DMARC Checker](https://apify.com/plainsight/email-security-audit): Google Workspace vs Microsoft 365, SPF/DKIM/DMARC grade, spoofable domains.
- [SEO & AI Visibility Audit](https://apify.com/plainsight/seo-ai-visibility-audit): on-page SEO plus which AI crawlers (ChatGPT, Perplexity, Claude) a site blocks.
- [Company Hiring Signals](https://apify.com/plainsight/company-hiring-signals): open roles by department for any list of company domains.

Found a missed or wrong detection? Open an issue on the Actor's **Issues** tab with the domain.

# Actor input Schema

## `domains` (type: `array`):

Domains, URLs or email addresses, one per line (e.g. stripe.com, https://www.notion.so/product, jane@acme.com). Duplicates and www. prefixes are handled automatically.

## `detectCompanyToolsFromDns` (type: `boolean`):

Also reveal SaaS tools the company has verified ownership with in DNS (e.g. HubSpot, Atlassian, Salesforce, Zoom, Figma, OpenAI, Microsoft 365). These are internal tools you cannot see on the website itself.

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

Hide detections below this confidence. Lower it to see weaker signals.

## `includeTechDetails` (type: `boolean`):

Include website, icon, pricing, confidence and evidence for each technology. Turn off for a smaller, spreadsheet-friendly output.

## `maxDomains` (type: `integer`):

Only process the first N domains (useful for a quick test).

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

How many websites to analyse in parallel.

## Actor input object example

```json
{
  "domains": [
    "stripe.com",
    "notion.so",
    "wordpress.org"
  ],
  "detectCompanyToolsFromDns": true,
  "minConfidence": 50,
  "includeTechDetails": true,
  "maxConcurrency": 25
}
```

# Actor output Schema

## `results` (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 = {
    "domains": [
        "stripe.com",
        "notion.so",
        "wordpress.org"
    ]
};

// Run the Actor and wait for it to finish
const run = await client.actor("plainsight/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 = { "domains": [
        "stripe.com",
        "notion.so",
        "wordpress.org",
    ] }

# Run the Actor and wait for it to finish
run = client.actor("plainsight/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 '{
  "domains": [
    "stripe.com",
    "notion.so",
    "wordpress.org"
  ]
}' |
apify call plainsight/tech-stack-detector --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,plainsight/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/HeniBbw5T8aZ1RTjQ/builds/TeRK0bLPU4ysv7IC6/openapi.json