# Subdomain finder: every subdomain of a domain, checked in DNS

**Use case:** 

Find the subdomains of any domain from public sources (crt.sh, HackerTarget, RapidDNS and CertSpotter) with no API key, each one checked live in DNS, one row per subdomain. Type a domain or paste a URL; full URLs are cleaned. Add your own API keys to search the other 50 sources too.

## Input

```json
{
  "domain": "apify.com",
  "sources": [
    "crtsh",
    "hackertarget",
    "rapiddns",
    "certspotter"
  ],
  "limit": 500,
  "dnsLookup": false,
  "dnsBrute": false,
  "takeOver": false,
  "screenshot": false,
  "shodan": false,
  "apiScan": false,
  "timeout": 1800,
  "start": 0,
  "useProxies": false,
  "quiet": true
}
```

## Output

```json
{
  "host": {
    "label": "Subdomain (host)",
    "format": "string"
  },
  "resolves": {
    "label": "Live now? (resolves)",
    "format": "boolean"
  },
  "ip": {
    "label": "IP address (ip)",
    "format": "string"
  },
  "domain": {
    "label": "Website researched (domain)",
    "format": "string"
  },
  "timestamp": {
    "label": "Found at (timestamp)",
    "format": "string"
  }
}
```

## How it works

### 1. Sign up on Apify or log in

The Email & Subdomain Finder - theHarvester OSINT | 54 Sources Actor is ready to run with the inputs already set for "Subdomain finder: every subdomain of a domain, checked in DNS". [Sign up or log in](https://console.apify.com/create-task-from-example/gk2GhCByenLeXQz8g) and you'll land in Apify Console with a copy of this exact task.

### 2. Start the "Subdomain finder: every subdomain of a domain, checked in DNS" task

The Email & Subdomain Finder - theHarvester OSINT | 54 Sources Actor will start running based on the input automatically. You can also change all the input fields, like website to research (domain), where to search (sources), and more, to match your specific use case.

### 3. Receive the "Subdomain finder: every subdomain of a domain, checked in DNS" output

Monitor the progress in real time. You will be notified as soon as your dataset is complete and ready for review. Each result includes data such as subdomain (host), live now? (resolves), IP address (ip), and more.

### 4. Integrate into your workflow

The final output is delivered in JSON, CSV, or Excel format, ready to be plugged into your workflow. You can also [run the "Subdomain finder: every subdomain of a domain, checked in DNS" task via API](https://apify.com/anshumanatrey/theharvester-osint.md).

## About this Actor

This example demonstrates how to use [Email & Subdomain Finder - theHarvester OSINT | 54 Sources](https://apify.com/anshumanatrey/theharvester-osint.md) with a specific input configuration. Visit the [Actor detail page](https://apify.com/anshumanatrey/theharvester-osint.md) to learn more, explore other use cases, and run it yourself.


## How to integrate an Actor?

This Task's input is already configured above. Use it as-is rather than inventing a new one.

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 full API examples (JavaScript, Python, CLI, MCP, OpenAPI), see this Task's Actor page: https://apify.com/anshumanatrey/theharvester-osint.md

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`).