StackPeek API Documentation

Free technology stack detection API. Detect CMS, frameworks, analytics, CDN, libraries, and more from any website. No API keys, no authentication required.

Base URL: https://stackpeek.dev/api/v1

Authentication

No authentication is required. The API is free and open for everyone. Simply make HTTP requests to the endpoints below.

POST /detect

POST /api/v1/detect

Detect technologies used by a website. Optionally filter by specific categories.

Request Body

Field	Type	Required	Description
`url`	string	required	The website URL to analyze (must include protocol)
`categories`	array	optional	Filter by specific categories (e.g. `["cms", "javascript-frameworks"]`). Omit to scan all categories.

Example Request

          
          
          
          cURL
        
curl -X POST "https://stackpeek.dev/api/v1/detect" \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://example.com",
    "categories": ["cms", "javascript-frameworks"]
  }'

Example Response

          
          
          
          JSON Response
        
{
  "status": "success",
  "data": {
    "url": "https://example.com",
    "scannedAt": "2026-02-14T10:30:00.000Z",
    "technologies": [
      {
        "name": "React",
        "category": "javascript-frameworks",
        "categoryLabel": "JavaScript Frameworks",
        "website": "https://react.dev",
        "version": "18.2.0",
        "confidence": 95,
        "evidence": ["html:data-reactroot", "script:react-dom"]
      },
      {
        "name": "WordPress",
        "category": "cms",
        "categoryLabel": "CMS",
        "website": "https://wordpress.org",
        "confidence": 100,
        "evidence": ["html:wp-content", "meta:generator"]
      }
    ],
    "meta": {
      "totalDetected": 12,
      "categoriesFound": 5,
      "scanDurationMs": 1420
    }
  }
}

GET /detect

GET /api/v1/detect

Detect technologies via GET request. URL passed as query parameter. No category filtering in GET variant.

Query Parameters

Param	Type	Required	Description
`url`	string	required	The website URL to analyze (URL-encoded)

Example Request

          
          cURL
        
curl "https://stackpeek.dev/api/v1/detect?url=https%3A%2F%2Fexample.com"

GET /categories

GET /api/v1/categories

Returns all technology categories with fingerprint counts.

Example Response

          
          
          
          JSON Response
        
{
  "status": "success",
  "data": [
    { "id": "cms", "label": "CMS", "count": 8 },
    { "id": "javascript-frameworks", "label": "JavaScript Frameworks", "count": 12 },
    { "id": "analytics", "label": "Analytics", "count": 15 },
    { "id": "cdn", "label": "CDN", "count": 6 }
  ]
}

GET /technologies

GET /api/v1/technologies

Returns all detectable technologies across all categories.

Example Response

          
          
          
          JSON Response
        
{
  "status": "success",
  "data": [
    {
      "name": "React",
      "category": "javascript-frameworks",
      "categoryLabel": "JavaScript Frameworks",
      "website": "https://react.dev",
      "hasVersionDetection": true
    },
    {
      "name": "WordPress",
      "category": "cms",
      "categoryLabel": "CMS",
      "website": "https://wordpress.org",
      "hasVersionDetection": true
    }
  ]
}

Response Format

All responses are JSON. Successful responses include "status": "success". Error responses include "error" and "message" fields.

Technology Object Structure

Field	Type	Description
`name`	string	Technology name (e.g. "React")
`category`	string	Category ID (e.g. "javascript-frameworks")
`categoryLabel`	string	Human-readable category (e.g. "JavaScript Frameworks")
`website`	string	Official website URL
`version`	string	Detected version (if available)
`confidence`	number	Detection confidence (0-100)
`evidence`	array	Fingerprint matches (e.g. ["html:data-reactroot"])

Available Categories

          
          Category IDs
        
cms, javascript-frameworks, backend-frameworks, css-frameworks,
analytics, cdn, web-servers, ecommerce, javascript-libraries,
marketing, payment, security, tag-managers, programming-languages,
seo, hosting, font-services, build-tools

Error Codes

Status	Meaning
`400`	Bad Request — Missing URL, Invalid URL, or Blocked URL (SSRF protection)
`404`	Not Found — Endpoint does not exist
`429`	Too Many Requests — Rate limit exceeded (30 req/min)
`500`	Internal Server Error — Something went wrong
`502`	Bad Gateway — Target site unreachable
`504`	Gateway Timeout — Target site timeout

Error Response Example

          
          400 Bad Request
        
{
  "error": "Missing URL",
  "message": "Provide a \"url\" field in the request body"
}

Rate Limits

The API applies rate limiting to protect service quality:

Limit	Value
Requests per minute	`30` per IP address
Window	`60 seconds` sliding window

When rate limited, the API returns a 429 status with a Retry-After header.

Rate limit headers are included in every response: RateLimit-Limit, RateLimit-Remaining, RateLimit-Reset.

cURL Example

          
          
          
          terminal
        
# Detect all technologies
curl "https://stackpeek.dev/api/v1/detect?url=https%3A%2F%2Fexample.com"

# Detect specific categories
curl -X POST "https://stackpeek.dev/api/v1/detect" \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://example.com",
    "categories": ["cms", "javascript-frameworks"]
  }'

# List all categories
curl "https://stackpeek.dev/api/v1/categories"

JavaScript Example

          
          
          
          app.js
        
// Detect all technologies
const response = await fetch(
  'https://stackpeek.dev/api/v1/detect?url=' +
  encodeURIComponent('https://example.com')
);
const data = await response.json();
console.log(data);

// Detect specific categories
const postResponse = await fetch('https://stackpeek.dev/api/v1/detect', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    url: 'https://example.com',
    categories: ['cms', 'javascript-frameworks']
  }),
});
const result = await postResponse.json();
console.log(result);

Python Example

          
          
          
          main.py
        
import requests

# Detect all technologies
response = requests.get(
    'https://stackpeek.dev/api/v1/detect',
    params={'url': 'https://example.com'}
)
data = response.json()
print(data)

# Detect specific categories
response = requests.post(
    'https://stackpeek.dev/api/v1/detect',
    json={
        'url': 'https://example.com',
        'categories': ['cms', 'javascript-frameworks']
    }
)
result = response.json()
print(result)