# Subdomain Finder (Certificate Transparency)

**Use case:** 

Subdomain Finder enumerates every subdomain of a domain from Certificate Transparency logs (crt.sh, Cert Spotter) and resolves each one — one row per subdomain, no proxies needed.

## Input

```json
{
  "domains": [
    "apify.com",
    "github.com"
  ],
  "resolveDns": true,
  "includeWildcards": false,
  "maxSubdomainsPerDomain": 500,
  "maxConcurrency": 5
}
```

## Output

```json
{
  "subdomain": {
    "label": "Subdomain",
    "format": "string"
  },
  "domain": {
    "label": "Domain",
    "format": "string"
  },
  "resolves": {
    "label": "Resolves",
    "format": "boolean"
  },
  "ipv4": {
    "label": "IPv4 addresses",
    "format": "array"
  },
  "cname": {
    "label": "CNAME",
    "format": "string"
  },
  "certificateCount": {
    "label": "Certificates",
    "format": "integer"
  },
  "issuers": {
    "label": "Issuers",
    "format": "array"
  },
  "firstSeen": {
    "label": "First seen",
    "format": "string"
  },
  "lastSeen": {
    "label": "Last seen",
    "format": "string"
  }
}
```

## About this Actor

This example demonstrates how to use [Subdomain Finder (Certificate Transparency)](https://apify.com/webdatatools/subdomain-finder.md) with a specific input configuration. Visit the [Actor detail page](https://apify.com/webdatatools/subdomain-finder.md) to learn more, explore other use cases, and run it yourself.


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

- **AI agents and MCP clients** — the [Apify MCP server](https://docs.apify.com/integrations/mcp.md) at `https://mcp.apify.com` (remote, streamable HTTP, OAuth on first use).
- **Agentic workflows and local Actor development** — [Agent Skills](https://apify.com/.well-known/agent-skills/index.json) with the [Apify CLI](https://docs.apify.com/cli/docs.md): `npm install -g apify-cli`, then `apify login`.
- **JavaScript/TypeScript projects** — the official [JS/TS client](https://docs.apify.com/api/client/js/docs.md): `npm install apify-client`.
- **Python projects** — the official [Python client](https://docs.apify.com/api/client/python/docs.md): `pip install apify-client`.
- **Any other language** — the [REST API](https://docs.apify.com/api/v2.md).

For full API examples (JavaScript, Python, CLI, MCP, OpenAPI), see this Task's Actor page: https://apify.com/webdatatools/subdomain-finder.md

For more details, see Apify documentation as [Markdown index](https://docs.apify.com/llms.txt) and [Markdown full-text](https://docs.apify.com/llms-full.txt).