# Subdomains Containing Letters

Matches records whose subdomain.contains_letter equals true.

Source: https://docs.deepinfo.com/reference/discovery/domain-search/examples/subdomain-contains-letter/

Last updated: 2026-09-26

---
`POST https://api.deepinfo.com/v1/discovery/domain-search?page_size=25`

Example 3 of 9 in **Filters › Subdomain** · [Domain Search Examples](/reference/discovery/domain-search/examples/) · endpoint: [Domain Search](/reference/discovery/domain-search/)

Tags: `field` `subdomain.contains_letter` · `operator` `eq`

Matches records whose `subdomain.contains_letter` equals `true`.

In the response, look at `results[].subdomain.contains_letter`.

## Request

| Parameter | In | Value |
|---|---|---|
| `page_size` | query | `25` |
| `filters.must[0].name` | body | `subdomain.contains_letter` |
| `filters.must[0].type` | body | `eq` |
| `filters.must[0].value` | body | `true` |

```bash
curl -X POST 'https://api.deepinfo.com/v1/discovery/domain-search?page_size=25' \
  -H 'apikey: YOUR_API_KEY' \
  -H 'Accept: application/json' \
  -H 'Content-Type: application/json' \
  -d '{
  "filters": {
    "must": [
      {
        "name": "subdomain.contains_letter",
        "type": "eq",
        "value": true
      }
    ]
  }
}'
```

## Response

### 200 · OK

> Shortened for this page: results: 3 of 25 shown

`Content-Type: application/json` · `ratelimit-limit: 1000` · `ratelimit-remaining: 999` · `ratelimit-reset: 1` · `x-ratelimit-limit-hour: 100000` · `x-ratelimit-limit-minute: 10000` · `x-ratelimit-limit-second: 1000` · `x-ratelimit-remaining-hour: 99977` · `x-ratelimit-remaining-minute: 9977` · `x-ratelimit-remaining-second: 999` · `deepinfo-request-id: 5f0c6a8e-1b2d-4c3e-9f4a-7b8c9d0e1f2a`

```json
{
  "page": 1,
  "page_size": 25,
  "result_count": 1507065921,
  "results": [
    {
      "punycode": "kwz.gov-l.sbs",
      "unicode": "kwz.gov-l.sbs",
      "is_idn": false,
      "subdomain": {
        "punycode": "kwz",
        "unicode": "kwz",
        "is_idn": false,
        "contains_letter": true,
        "contains_number": false,
        "contains_hyphen": false,
        "length": 3
      },
      "subdomain_last": {
        "punycode": "kwz",
        "unicode": "kwz",
        "is_idn": false,
        "contains_letter": true,
        "contains_number": false,
        "contains_hyphen": false,
        "length": 3
      },
      "subdomain_root": {
        "punycode": "kwz",
        "unicode": "kwz",
        "is_idn": false,
        "contains_letter": true,
        "contains_number": false,
        "contains_hyphen": false,
        "length": 3
      },
      "name": {
        "punycode": "kwz.gov-l",
        "unicode": "kwz.gov-l",
        "is_idn": false,
        "contains_letter": true,
        "contains_number": false,
        "contains_hyphen": true,
        "length": 8,
        "lang": "en",
        "keywords": [
          "kwz",
          "gov"
        ],
        "keyword_count": 2,
        "latinized": [],
        "contains_confusable": false
      },
      "domain": {
        "punycode": "gov-l.sbs",
        "unicode": "gov-l.sbs",
        "is_idn": false,
        "name": {
          "punycode": "gov-l",
          "unicode": "gov-l",
          "is_idn": false,
          "contains_letter": true,
          "contains_number": false,
          "contains_hyphen": true,
          "length": 5,
          "lang": "en",
          "keywords": [
            "gov"
          ],
          "keyword_count": 1
        },
        "extension": {
          "punycode": "sbs",
          "unicode": "sbs",
          "is_idn": false
        },
        "extension_root": {
          "punycode": "sbs",
          "unicode": "sbs",
          "is_idn": false
        },
        "extension_sub": null,
        "extension_type": 1,
        "reserved": null,
        "premium": null,
        "registered": true,
        "whois": {
          "create_date": "2026-03-23T20:09:45Z",
          "update_date": "2026-03-28T20:12:09Z",
          "expiry_date": "2027-03-23T23:59:59Z",
          "registrar": "dynadot llc",
          "registrant": {
            "name": null,
            "organization": null,
            "street": null,
            "city": null,
            "state": null,
            "postal_code": null,
            "country": null,
            "phone": null,
            "email": null
          },
          "name_servers": [
            "ns1.dyna-ns.net",
            "ns2.dyna-ns.net"
          ],
          "domain_status": [
            "clienttransferprohibited",
            "servertransferprohibited"
          ],
          "whois_server": "whois.nic.sbs",
          "check_date": "2026-04-02T21:09:55Z"
        },
        "whois_normalized": {
          "registrant": null
        },
        "whois_last_check_date": "2026-04-02T21:09:55Z",
        "whois_create_date_historical": null,
        "whois_last_change_date": "2026-04-02T21:10:39Z",
        "whois_registrant_email_historical": null,
        "whois_privacy_enabled": null,
        "dns": {
          "a": {
            "update_date": "2026-09-02T04:57:07Z",
            "ip_addresses": [
              "54.215.31.113"
            ]
          }
        },
        "dns_last_change_date": "2026-07-23T01:12:31Z",
        "ip_history": null,
        "ssl": {
          "validity": {
            "start_date": "2026-07-22T13:18:00Z",
            "end_date": "2026-10-20T13:17:59Z"
          },
          "serial_number": "497912472515534737262716277415687360969386",
          "check_date": "2026-08-18T14:44:46Z"
        },
        "ssl_last_change_date": "2026-08-18T14:45:31Z"
      },
      "type": 2,
      "subdomain_level_count": 1,
      "dns": {
        "a": {
          "update_date": "2026-09-14T22:36:59Z",
          "ip_addresses": [
            "43.198.219.115"
          ]
        },
        "aaaa": {
          "update_date": "2026-09-14T22:36:59Z",
          "ip_addresses": []
        },
        "ns": {
          "update_date": "2026-09-14T22:36:59Z",
          "name_servers": []
        },
        "mx": {
          "update_date": "2026-09-14T22:36:59Z",
          "mail_servers": []
        },
        "soa": {
          "update_date": "2026-09-14T22:36:59Z",
          "mnames": [],
          "rnames": [],
          "rname_emails": []
        },
        "txt": {
          "update_date": "2026-09-14T22:36:59Z",
          "values": []
        },
        "cname": {
          "update_date": "2026-09-14T22:36:59Z",
          "values": []
        },
        "others": []
      },
      "dns_last_change_date": "2026-09-14T22:37:02Z",
      "ip_history": [
        "43.198.219.115"
      ],
      "ssl": null,
      "ssl_last_change_date": null,
      "webdata": null
    },
    {
      "punycode": "www.rewardpen.xyz",
      "unicode": "www.rewardpen.xyz",
      "is_idn": false,
      "subdomain": {
        "punycode": "www",
        "unicode": "www",
        "is_idn": false,
        "contains_letter": true,
        "contains_number": false,
        "contains_hyphen": false,
        "length": 3
      },
      "subdomain_last": {
        "punycode": "www",
        "unicode": "www",
        "is_idn": false,
        "contains_letter": true,
        "contains_number": false,
        "contains_hyphen": false,
        "length": 3
      },
      "subdomain_root": {
        "punycode": "www",
        "unicode": "www",
        "is_idn": false,
        "contains_letter": true,
        "contains_number": false,
        "contains_hyphen": false,
        "length": 3
      },
      "name": {
        "punycode": "www.rewardpen",
        "unicode": "www.rewardpen",
        "is_idn": false,
        "contains_letter": true,
        "contains_number": false,
        "contains_hyphen": false,
        "length": 12,
        "lang": "en",
        "keywords": [
          "www",
          "reward",
          "pen"
        ],
        "keyword_count": 3,
        "latinized": [],
        "contains_confusable": false
      },
      "domain": {
        "punycode": "rewardpen.xyz",
        "unicode": "rewardpen.xyz",
        "is_idn": false,
        "name": {
          "punycode": "rewardpen",
          "unicode": "rewardpen",
          "is_idn": false,
          "contains_letter": true,
          "contains_number": false,
          "contains_hyphen": false,
          "length": 9,
          "lang": "en",
          "keywords": [
            "reward",
            "pen"
          ],
          "keyword_count": 2
        },
        "extension": {
          "punycode": "xyz",
          "unicode": "xyz",
          "is_idn": false
        },
        "extension_root": {
          "punycode": "xyz",
          "unicode": "xyz",
          "is_idn": false
        },
        "extension_sub": null,
        "extension_type": 1,
        "reserved": null,
        "premium": null,
        "registered": true,
        "whois": {
          "create_date": "2026-09-12T10:03:56Z",
          "update_date": null,
          "expiry_date": "2027-09-12T23:59:59Z",
          "registrar": "gmo internet group, inc. d/b/a onamae.com",
          "registrant": {
            "name": null,
            "organization": null,
            "street": null,
            "city": null,
            "state": null,
            "postal_code": null,
            "country": null,
            "phone": null,
            "email": null
          },
          "name_servers": [
            "ns5.afternic.com",
            "ns6.afternic.com",
            "verification-gakbzzzqmt6gkcplw4efpp.ns101.verify.hn"
          ],
          "domain_status": [
            "addperiod",
            "servertransferprohibited"
          ],
          "whois_server": "whois.nic.xyz",
          "check_date": "2026-09-13T07:53:38Z"
        },
        "whois_normalized": {
          "registrant": null
        },
        "whois_last_check_date": "2026-09-13T07:53:38Z",
        "whois_create_date_historical": null,
        "whois_last_change_date": "2026-09-13T07:56:21Z",
        "whois_registrant_email_historical": null,
        "whois_privacy_enabled": null,
        "dns": {
          "a": {
            "update_date": "2026-09-13T02:17:47Z",
            "ip_addresses": [
              "13.248.169.48",
              "76.223.54.146"
            ]
          }
        },
        "dns_last_change_date": "2026-09-13T02:17:48Z",
        "ip_history": null,
        "ssl": {
          "validity": {
            "start_date": "2026-09-14T04:13:23Z",
            "end_date": "2027-03-31T04:13:23Z"
          },
          "serial_number": "13562407821581085115",
          "check_date": "2026-09-14T17:25:46Z"
        },
        "ssl_last_change_date": "2026-09-14T17:27:10Z"
      },
      "type": 2,
      "subdomain_level_count": 1,
      "dns": {
        "a": {
          "update_date": "2026-09-14T22:37:05Z",
          "ip_addresses": [
            "13.248.169.48",
            "76.223.54.146"
          ]
        },
        "aaaa": {
          "update_date": "2026-09-14T22:37:05Z",
          "ip_addresses": []
        },
        "ns": {
          "update_date": "2026-09-14T22:37:05Z",
          "name_servers": [
            "ns5.afternic.com",
            "ns6.afternic.com"
          ]
        },
        "mx": {
          "update_date": "2026-09-14T22:37:05Z",
          "mail_servers": []
        },
        "soa": {
          "update_date": "2026-09-14T22:37:05Z",
          "mnames": [
            "ns5.afternic.com"
          ],
          "rnames": [
            "dns.jomax.net"
          ],
          "rname_emails": [
            "user@jomax.net"
          ]
        },
        "txt": {
          "update_date": "2026-09-14T22:37:05Z",
          "values": [
            "\"v=spf1 -all\""
          ]
        },
        "cname": {
          "update_date": "2026-09-14T22:37:05Z",
          "values": []
        },
        "others": []
      },
      "dns_last_change_date": "2026-09-14T22:37:06Z",
      "ip_history": [
        "13.248.169.48",
        "76.223.54.146"
      ],
      "ssl": null,
      "ssl_last_change_date": null,
      "webdata": null
    },
    {
      "punycode": "apps.zhuanei.com",
      "unicode": "apps.zhuanei.com",
      "is_idn": false,
      "subdomain": {
        "punycode": "apps",
        "unicode": "apps",
        "is_idn": false,
        "contains_letter": true,
        "contains_number": false,
        "contains_hyphen": false,
        "length": 4
      },
      "subdomain_last": {
        "punycode": "apps",
        "unicode": "apps",
        "is_idn": false,
        "contains_letter": true,
        "contains_number": false,
        "contains_hyphen": false,
        "length": 4
      },
      "subdomain_root": {
        "punycode": "apps",
        "unicode": "apps",
        "is_idn": false,
        "contains_letter": true,
        "contains_number": false,
        "contains_hyphen": false,
        "length": 4
      },
      "name": {
        "punycode": "apps.zhuanei",
        "unicode": "apps.zhuanei",
        "is_idn": false,
        "contains_letter": true,
        "contains_number": false,
        "contains_hyphen": false,
        "length": 11,
        "lang": "en",
        "keywords": [
          "apps",
          "zhuan",
          "ei"
        ],
        "keyword_count": 3,
        "latinized": [],
        "contains_confusable": false
      },
      "domain": {
        "punycode": "zhuanei.com",
        "unicode": "zhuanei.com",
        "is_idn": false,
        "name": {
          "punycode": "zhuanei",
          "unicode": "zhuanei",
          "is_idn": false,
          "contains_letter": true,
          "contains_number": false,
          "contains_hyphen": false,
          "length": 7,
          "lang": "en",
          "keywords": [
            "zhuan",
            "ei"
          ],
          "keyword_count": 2
        },
        "extension": {
          "punycode": "com",
          "unicode": "com",
          "is_idn": false
        },
        "extension_root": {
          "punycode": "com",
          "unicode": "com",
          "is_idn": false
        },
        "extension_sub": null,
        "extension_type": 1,
        "reserved": null,
        "premium": null,
        "registered": true,
        "whois": {
          "create_date": "2012-10-09T18:31:01Z",
          "update_date": "2026-07-30T06:59:22Z",
          "expiry_date": "2026-10-09T18:31:01Z",
          "registrar": "namecheap, inc.",
          "registrant": {
            "name": "redacted for privacy purposes",
            "organization": "privacy service provided by withheld for privacy llc",
            "street": "16192 coastal highway",
            "city": "lewes",
            "state": "delaware",
            "postal_code": "19958",
            "country": "us",
            "phone": "+1.3022061391",
            "email": "user@withheldforprivacy.com"
          },
          "name_servers": [
            "ns1.parkingcrew.net",
            "ns2.parkingcrew.net"
          ],
          "domain_status": [
            "ok"
          ],
          "whois_server": "whois.namecheap.com",
          "check_date": "2026-09-12T09:17:16Z"
        },
        "whois_normalized": {
          "registrant": {
            "organization": "privacyserviceprovidedbywithheldforprivacyllc",
            "phone": "13022061391",
            "email": "user@withheldforprivacy.com",
            "email_fqdn_apex": "withheldforprivacy.com",
            "email_domain_apex": "withheldforprivacy.com"
          }
        },
        "whois_last_check_date": "2026-09-12T09:17:16Z",
        "whois_create_date_historical": null,
        "whois_last_change_date": "2026-09-12T09:19:43Z",
        "whois_registrant_email_historical": null,
        "whois_privacy_enabled": true,
        "dns": {
          "a": {
            "update_date": "2026-09-11T08:31:03Z",
            "ip_addresses": [
              "104.247.81.99"
            ]
          }
        },
        "dns_last_change_date": "2026-08-31T10:13:01Z",
        "ip_history": null,
        "ssl": {
          "validity": {
            "start_date": "2020-07-20T00:00:00Z",
            "end_date": "2022-09-18T12:00:00Z"
          },
          "serial_number": "4055344257218010203087439766661402608",
          "check_date": "2021-09-19T08:47:52Z"
        },
        "ssl_last_change_date": "2025-12-24T18:19:11Z"
      },
      "type": 2,
      "subdomain_level_count": 1,
      "dns": {
        "a": {
          "update_date": "2026-09-07T19:33:29Z",
          "ip_addresses": [
            "104.247.81.99"
          ]
        },
        "aaaa": {
          "update_date": "2026-09-07T19:33:29Z",
          "ip_addresses": []
        },
        "ns": {
          "update_date": "2026-09-07T19:33:29Z",
          "name_servers": [
            "ns1.parkingcrew.net",
            "ns2.parkingcrew.net"
          ]
        },
        "mx": {
          "update_date": "2026-09-07T19:33:29Z",
          "mail_servers": [
            "mail.h-email.net"
          ]
        },
        "soa": {
          "update_date": "2026-09-07T19:33:29Z",
          "mnames": [
            "ns1.parkingcrew.net"
          ],
          "rnames": [
            "hostmaster.apps.zhuanei.com"
          ],
          "rname_emails": [
            "user@apps.zhuanei.com"
          ]
        },
        "txt": {
          "update_date": "2026-09-07T19:33:29Z",
          "values": [
            "\"v=spf1 ip6:fd1b:212c:a5f9::/48 -all\""
          ]
        },
        "cname": {
          "update_date": "2026-09-07T19:33:29Z",
          "values": []
        },
        "others": []
      },
      "dns_last_change_date": "2026-09-09T03:49:45Z",
      "ip_history": [
        "104.247.81.54",
        "104.247.81.99"
      ],
      "ssl": null,
      "ssl_last_change_date": null,
      "webdata": {
        "connection_status": "timeout",
        "html": null,
        "http": null
      }
    }
  ]
}
```

## Related Examples

- [Internationalized Subdomains](/reference/discovery/domain-search/examples/subdomain-is-idn/)
- [Subdomains Containing Digits](/reference/discovery/domain-search/examples/subdomain-contains-number/)
- [One Subdomain Across Domains](/reference/discovery/domain-search/examples/subdomain/)
- [Subdomains Containing a Hyphen](/reference/discovery/domain-search/examples/subdomain-contains-hyphen/)
- [Last Subdomain Label](/reference/discovery/domain-search/examples/subdomain-last/)
- [Root Subdomain Label](/reference/discovery/domain-search/examples/subdomain-root/)