---
title: Free Subdomains
description: What free subdomain and dynamic DNS services are, and why only the names beneath them are flagged.
---

Some services hand out subdomains of their own domain to the public, for free: dynamic DNS providers like `duckdns.org` and free subdomain services like `us.kg`. Unlike an ordinary subdomain, which belongs to whoever owns the parent domain, each name under one of these namespaces is controlled by a different, unrelated person, and new ones can be created instantly.

`free_subdomain` is `true` when the domain sits under one of these namespaces. The parent domain itself is not flagged: it's an ordinary registered domain, owned and controlled by the service operator; only the names beneath it are given away.

The field is returned by the [domain](/docs/api/domain-endpoint) and [email](/docs/api/email-endpoint) endpoints, and is available in Gates as `domain.free_subdomain`.

## Examples

| Domain | `free_subdomain` | Why |
|--------|------------------|-----|
| `alice.duckdns.org` | `true`  | A name handed out under the `duckdns.org` dynamic DNS service |
| `duckdns.org`       | `false` | The operator's own registered domain, not a handed-out name |
| `myapp.us.kg`       | `true`  | A name handed out under a free subdomain service |
| `github.com`        | `false` | An ordinary registered domain |

## Relationship to disposable domains

`free_subdomain` and `disposable` are independent: a free subdomain is not necessarily disposable, and a domain can be both.