---
id: "fqdn"
kind: "datatype"
status: "stable"
is_pii: false
categories: ["internet"]
langs: ["common"]
quality: 100
url: "http://registry.apicrafter.io/datatype/fqdn"
---

# Fully qualified domain name (FQDN) (`fqdn`)

Complete domain name of a host or zone, written as labels separated by dots from the host up to the top-level domain, such as www.example.com. A trailing dot stands for the DNS root and is left out in most data. Each label has 1 to 63 letters, digits or hyphens and does not start or end with a hyphen, and the whole name has at most 253 characters (RFC 1035, RFC 1123). Internationalized names are stored as Punycode labels that start with xn--. The regexp requires at least two labels and rejects an all-numeric last label, so IPv4 addresses do not match.

- Personal data (PII): no
- Categories: Internet (internet)
- Countries: global
- Languages: Common to most languages (common)
- Classification: identifier

## Detection

Regular expression (Python `re`):

```
^(?=.{1,253}\.?$)(?:[A-Za-z0-9](?:[A-Za-z0-9-]{0,61}[A-Za-z0-9])?\.)+(?![0-9]+\.?$)[A-Za-z0-9](?:[A-Za-z0-9-]{0,61}[A-Za-z0-9])?\.?$
```

## Examples

- `ec2-35-160-210-253.us-west-2.compute.amazonaws.com` — Amazon web services ec2 server
- `xn--kxae4bafwg.xn--pxaix.gr` — Greek language national domain name
- `did:web:w3c-ccg.github.io` (invalid example) — Decentralized identifier (DID); a colon is not allowed in a label
- `https://www.example.com/path` (invalid example) — URL; a domain name has no scheme or path
- `my host.example.com` (invalid example) — A label with a space
- `ec2-35-160-210-253.us-west-2-.compute.amazonaws.com` (invalid example) — A label that ends with a hyphen
- `192.0.2.1` (invalid example) — IPv4 address; the top-level label must not be all-numeric

## Mappings

- google_dlp: `DOMAIN_NAME`
- wikidata: `P13337`

## Metacrafter rules

2 rules: 1 match the field name, 1 match values.

- `fqdnbyvalidators` (data, `common/commonurl.yaml`)
- `fqdnbyknown` (field, `common/internet.yaml`)

## Supported by tools

- `collibra`
- `googledlp`
- `metacrafter`
- `talend`

## Translations

- ru: Полное доменное имя (FQDN): Полное доменное имя узла: метки через точку до домена верхнего уровня, например www.example.com.

## Sources

- wikipedia: <https://en.wikipedia.org/wiki/Fully_qualified_domain_name>
- wikidata: <https://www.wikidata.org/wiki/Property:P13337>
- doc: <https://www.rfc-editor.org/rfc/rfc1035>
- doc: <https://www.rfc-editor.org/rfc/rfc1123>

## Quality

Score 100/100.

JSON: <http://registry.apicrafter.io/api/v1/datatypes/fqdn.json> · Edit: <https://github.com/apicrafter/metacrafter-registry/edit/main/data/datatypes/any/internet/fqdn.yaml>