Free Tech Stack Checker

A website's own page and headers say a great deal about what it runs on.

A tech stack check returns these fields, and each one answers a different question.

This is an invented result for a made-up shop, laid out the way a real one comes back. Every field shown is free on this page, and a free trial adds whole lists by CSV upload and the same check through the API.

Checking a website's tech stack takes three steps and no signup.

One check travels from your browser to the website and back in four steps.

This is the path a single check takes. The address is tested first, so a private or internal address is never visited.

Bulk tech stack checks read a whole list of websites with one CSV file.

The free tool checks one website at a time. With a 1Lookup account you upload a CSV file in the dashboard, pick the column that holds the websites and download the same file back with the technology columns filled in on every row. These rows are invented.

domain
sample-shop.example.com
sample-store.example.net
no-such-site.example.org

• 1 credit for each website that answers, about half a cent on Starter, and nothing for a site that blocks the check, does not exist or does not answer.
• Up to 2 million rows in one CSV file.
• One column per group (CMS, shop, analytics, marketing, hosting and more), so the file sorts and filters by technology.

The Tech Stack Lookup API returns the same technologies as JSON from one request.

Send a domain to the endpoint with your API key. A site that answers costs 1 credit, and a site that blocks the check, does not exist or does not answer costs 0. The groups are flat fields in classification, and each technology with its version and categories is in insights.tech_stack_result.

curl -X POST https://app.1lookup.io/api/v1/tech-stack-lookup \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"domain": "sample-shop.example.com"}'

import requests

response = requests.post(
    "https://app.1lookup.io/api/v1/tech-stack-lookup",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={"domain": "sample-shop.example.com"},
)
data = response.json()["data"]
print(data["classification"]["cms"])

const response = await fetch('https://app.1lookup.io/api/v1/tech-stack-lookup', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({ domain: 'sample-shop.example.com' })
})
const { data } = await response.json()
console.log(data.classification.cms)

{
  "success": true,
  "data": {
    "classification": {
      "found": true,
      "query": "sample-shop.example.com",
      "final_url": "https://sample-shop.example.com/",
      "technology_count": 13,
      "cms": "WordPress 7.2",
      "ecommerce": "WooCommerce 11.4.0 | Stripe",
      "analytics": "Google Tag Manager | Google Analytics GA4",
      "hosting": "Cloudflare | Nginx 1.25.3",
      "email_provider": "Google Workspace",
      "dns_host": "Cloudflare",
      "detected_from": "detected from the site's headers, HTML and DNS"
    },
    "insights": {
      "tech_stack_result": {
        "technologies": [
          { "name": "WordPress", "version": "7.2", "group": "CMS and site builders", "implied": false }
        ]
      }
    },
    "metadata": { "credits_used": 1, "cache_hit": false }
  }
}

For whole lists of websites from a CSV file, with every technology on each row, see our Tech Stack Lookup API.

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