# Subdomain Finder

GET /discovery/subdomain-finder: Finds all known subdomains of a domain.

Source: https://docs.deepinfo.com/reference/discovery/subdomain-finder/

Last updated: 2026-09-27

---
`GET https://api.deepinfo.com/v1/discovery/subdomain-finder`

Finds all known subdomains of a domain.

## Authentication

Send your API key in the `apikey` request header.

## Query Parameters

| Parameter | Required | Description | Example |
|---|---|---|---|
| `domain` | Required |  | `deepinfo.com` |
| `export` | Optional | Default `false`. | `true` |
| `export_format` | Optional | One of: `json`, `csv`. | `csv` |
| `export_scope` | Optional | One of: `basic`, `default`, `extended`. | `basic` |
| `ordering` | Optional |  |  |
| `page` | Optional | Min `1`, max `400`. Default `1`. | `1` |
| `page_size` | Optional | Min `25`, max `100`. Default `100`. | `100` |

## Response Fields

| Field | Type | Description |
|---|---|---|
| `page` | integer |  |
| `page_size` | integer |  |
| `result_count` | integer |  |
| `results` | array of object |  |
| `results[].punycode` | string |  |
| `results[].unicode` | string |  |
| `results[].is_idn` | boolean |  |
| `results[].subdomain` | object |  |
| `results[].subdomain_last` | object |  |
| `results[].subdomain_root` | object |  |
| `results[].name` | object |  |
| `results[].domain` | object |  |
| `results[].type` | integer |  |
| `results[].subdomain_level_count` | integer |  |
| `results[].dns` | object |  |
| `results[].dns_last_change_date` | string | date-time |
| `results[].ip_history` | array of string |  |
| `results[].ssl` | object |  |
| `results[].ssl_last_change_date` | string | date-time |
| `results[].webdata` | object |  |

Paginated. See [Getting Started → Pagination](/getting-started/pagination/).

## Examples

### 200 · OK

```bash
curl 'https://api.deepinfo.com/v1/discovery/subdomain-finder?export=true&export_format=csv&export_scope=basic&domain=deepinfo.com' \
  -H 'apikey: YOUR_API_KEY' \
  -H 'Accept: application/json'
```

`Content-Type: text/csv; charset=utf-8` · `deepinfo-request-id: 5f0c6a8e-1b2d-4c3e-9f4a-7b8c9d0e1f2a`

```
page,page_size,result_count,results.punycode,results.unicode,results.domain.whois.create_date,results.domain.whois.update_date,results.domain.whois.expiry_date,results.domain.whois.registrar,results.domain.whois.registrant.name,results.domain.whois.registrant.organization,results.domain.whois.registrant.street,results.domain.whois.registrant.city,results.domain.whois.registrant.state,results.domain.whois.registrant.postal_code,results.domain.whois.registrant.country,results.domain.whois.registrant.phone,results.domain.whois.registrant.email,results.domain.whois.name_servers,results.domain.whois.domain_status,results.domain.whois.whois_server,results.domain.whois.check_date,results.domain.whois_last_change_date,results.dns.a.update_date,results.dns.a.ip_addresses,results.dns.aaaa.update_date,results.dns.aaaa.ip_addresses,results.dns.ns.update_date,results.dns.ns.name_servers,results.dns.mx.update_date,results.dns.mx.mail_servers,results.dns.soa.update_date,results.dns.soa.mnames,results.dns.soa.rnames,results.dns.soa.rname_emails,results.dns.cname.update_date,results.dns.cname.values,results.ssl.serial_number,results.ssl.fingerprint.sha256,results.ssl.fingerprint.sha1,results.ssl.fingerprint.md5,results.ssl.validity.start_date,results.ssl.validity.end_date,results.ssl.validity.length,results.ssl.signature.is_self_signed,results.ssl.signature.is_valid,results.ssl.signature.algorithm.name,results.ssl.issuer_dn,results.ssl.subject_dn,results.ssl.check_date,results.ssl_last_change_date,results.webdata.connection_status,results.webdata.http.status_code_first,results.webdata.http.status_code_last,results.webdata.http.external_redirection,results.webdata.http.final_url,results.webdata.http.final_fqdn,results.webdata.http.final_domain
1,100,11,calendar.deepinfo.com,calendar.deepinfo.com,2001-06-05T02:57:08Z,2025-08-19T07:33:45Z,2028-10-20T11:59:59Z,godaddy online services cayman islands ltd.,,,,,,,,,,may.ns.cloudflare.com;simon.ns.cloudflare.com,clientdeleteprohibited;clientrenewprohibited;clienttransferprohibited;clientupdateprohibited,whois.uniregistrar.com,2026-08-12T13:01:51Z,2026-08-12T09:44:55Z,2026-06-12T20:04:45Z,104.26.10.21;104.26.11.21;172.67.70.198,2026-06-12T20:04:45Z,2606:4700:20::681a:a15;2606:4700:20::681a:b15;2606:4700:20::ac43:46c6,2026-06-12T20:04:45Z,,2026-06-12T20:04:45Z,,2026-06-12T20:04:45Z,,,,2026-06-12T20:04:45Z,,294025305291592463081728235283740205912,89270a8f0514627a26928712e92cbefbb5d3f66e18df0bc5a12ed8e772c883d9,a9fcc445c4ef545eaf05decca222218d44c8fbab,d8cd8dd958879cecfeae74a98b5f1fc6,2026-06-24T13:16:53Z,2026-09-22T14:16:46Z,7779593,False,True,sha256,"CN=WE1,O=Google Trust Services,C=US",CN=deepinfo.com,2026-08-12T12:08:51Z,2026-08-09T04:21:13Z,success,301,200,True,https://www.google.com/a/deepinfo.com/ServiceLogin?service=cl&continue=https://calendar.google.com/calendar/&followup=https://calendar.google.com/calendar/&osid=1&passive=1209600,www.google.com,google.com
1,100,11,deepinfo.com,deepinfo.com,2001-06-05T02:57:08Z,2025-08-19T07:33:45Z,2028-10-20T11:59:59Z,godaddy online services cayman islands ltd.,registration private,"domains by proxy, llc",domainsbyproxy.com,tempe,arizona,85281,us,+1.4806242599,https://www.godaddy.com/whois/results.aspx?domain=deepinfo.com&action=contactdomainowner,may.ns.cloudflare.com;simon.ns.cloudflare.com,clientdeleteprohibited;clientrenewprohibited;clienttransferprohibited;clientupdateprohibited,whois.uniregistrar.com,2026-09-22T15:14:21Z,2026-09-22T15:17:20Z,2026-09-22T15:14:25Z,104.26.10.21;104.26.11.21;172.67.70.198,2026-09-18T05:41:26Z,2606:4700:20::681a:a15;2606:4700:20::681a:b15;2606:4700:20::ac43:46c6,2026-09-18T05:41:26Z,may.ns.cloudflare.com;simon.ns.cloudflare.com,2026-09-22T15:14:25Z,aspmx.l.google.com;alt1.aspmx.l.google.com;alt2.aspmx.l.google.com;alt3.aspmx.l.google.com;alt4.aspmx.l.google.com,2026-09-18T05:41:26Z,may.ns.cloudflare.com,dns.cloudflare.com,user@cloudflare.com,2026-09-18T05:41:26Z,,175099252490783179325599447426535789523,12a3374625c71344dca023d3fd679c8603b98712dc07b5489dde7fd65ad8ce50,5102c880b9f106836e519b298180d61b676159c8,d168f284acc2bd12ef0942ca7b8437ce,2026-08-22T16:13:55Z,2026-11-20T17:13:40Z,7779585,False,True,sha256,"CN=WE1,O=Google Trust Services,C=US",CN=deepinfo.com,2026-09-22T15:35:16Z,2026-09-18T15:26:10Z,success,301,200,False,https://www.deepinfo.com/,www.deepinfo.com,deepinfo.com
1,100,11,api.deepinfo.com,api.deepinfo.com,2001-06-05T02:57:08Z,2025-08-19T07:33:45Z,2028-10-20T11:59:59Z,godaddy online services cayman islands ltd.,,,,,,,,,,may.ns.cloudflare.com;simon.ns.cloudflare.com,clientdeleteprohibited;clientrenewprohibited;clienttransferprohibited;clientupdateprohibited,whois.uniregistrar.com,2026-08-12T21:25:04Z,2026-08-12T21:27:22Z,2026-08-06T10:36:39Z,104.26.10.21;104.26.11.21;172.67.70.198,2026-08-06T10:36:39Z,2606:4700:20::681a:a15;2606:4700:20::681a:b15;2606:4700:20::ac43:46c6,2026-08-06T10:36:39Z,,2026-08-06T10:36:39Z,,2026-08-06T10:36:39Z,,,,2026-08-06T10:36:39Z,,294025305291592463081728235283740205912,89270a8f0514627a26928712e92cbefbb5d3f66e18df0bc5a12ed8e772c883d9,a9fcc445c4ef545eaf05decca222218d44c8fbab,d8cd8dd958879cecfeae74a98b5f1fc6,2026-06-24T13:16:53Z,2026-09-22T14:16:46Z,7779593,False,True,sha256,"CN=WE1,O=Google Trust Services,C=US",CN=deepinfo.com,2026-08-12T12:08:51Z,2026-08-12T06:41:32Z,success,301,520,False,https://api.deepinfo.com/,api.deepinfo.com,deepinfo.com
…
```

### 400 · Invalid Parameter (invalid export=notabool)

```bash
curl 'https://api.deepinfo.com/v1/discovery/subdomain-finder?export=notabool&domain=deepinfo.com' \
  -H 'apikey: YOUR_API_KEY' \
  -H 'Accept: application/json'
```

`Content-Type: application/json` · `deepinfo-request-id: 5f0c6a8e-1b2d-4c3e-9f4a-7b8c9d0e1f2a`

```json
{
  "code": 10400,
  "parameters": [
    {
      "param": "export",
      "details": [
        "Must be a valid boolean."
      ]
    }
  ],
  "solution": "https://docs.deepinfo.com/reference/"
}
```

## Worked Examples

Worked examples of this endpoint, each on its own page with the exact request and its response: [Subdomain Finder Examples](/reference/discovery/subdomain-finder/examples/).

- [Every Subdomain of a Domain](/reference/discovery/subdomain-finder/examples/default/): Every known subdomain of deepinfo.com: 11 records, the domain itself included.
- [A Domain With Many Subdomains](/reference/discovery/subdomain-finder/examples/many-subdomains/): Every known subdomain of google.com, sorted by name: 76,911 records, starting with Google service hosts under mail.sandbox and clients6.
- [Most Recent Certificate Change First](/reference/discovery/subdomain-finder/examples/ordering-ssl-last-change-date-desc/): The subdomains of deepinfo.com, the most recent certificate change first (`ordering=-ssl_last_change_date`).