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Domain API · Free

Subdomain Finder
API

Enumerate subdomains for a target domain by querying Certificate Transparency logs (crt.sh) and DNS resolution. Returns deduplicated, sorted list.

Read the docsTry the visual tool

Free. No API key. CORS-enabled. Rate-limited per IP.

GEThttps://api.domainee.dev/v1/tools/subdomain-finder?domain=domainee.dev

Enumerate subdomains for a target domain by querying Certificate Transparency logs (crt.sh) and DNS resolution. Returns deduplicated, sorted list.

Free. No API key required. CORS-enabled. Rate-limited per IP at 30/min and 500/day.

Parameters

NameInTypeDescription
domainrequiredquerystring
Apex domain to enumerate subdomains for.
example: domainee.dev

Example request

curl
curl -s "https://api.domainee.dev/v1/tools/subdomain-finder?domain=domainee.dev" | jq

Example response

response.json
{
  "ok": true,
  "data": {
    "domain": "domainee.dev",
    "subdomains": [
      "api.domainee.dev",
      "edge.domainee.dev",
      "mcp.domainee.dev",
      "www.domainee.dev"
    ],
    "count": 4,
    "source": "certificate-transparency"
  }
}

Other languages

fetch.js
const res = await fetch("https://api.domainee.dev/v1/tools/subdomain-finder?domain=domainee.dev");
const { ok, data } = await res.json();
requests.py
import requests
r = requests.get(
    "https://api.domainee.dev/v1/tools/subdomain-finder",
    params={"domain":"domainee.dev"},
)
data = r.json()["data"]

Rate limits & errors

  • 30 requests/minute and 500 requests/day per IP. Exceeding either returns HTTP 429 with a Retry-After header.
  • All responses are JSON with the envelope { "ok": true, "data": {...} } on success or { "ok": false, "error": { "code", "message" } } on failure.
  • code values are stable; safe to switch on programmatically. message is human-friendly and may change.
Prefer a UI?

Try the subdomain finder in your browser →

No code, no curl. Type a domain, get a result.

Full reference

Documentation for /v1/tools/subdomain-finder →

All parameters, error codes, edge cases.

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