---
title: "Checks to see if a username is available on the server."
method: GET
path: "/_matrix/client/v3/register/available"
tags: ["Account management"]
---

# Checks to see if a username is available on the server.

`GET /_matrix/client/v3/register/available`

## Request

- Base URL: `https://matrix.org`
- URL: `https://matrix.org/_matrix/client/v3/register/available`
- Auth: none declared
- TypeScript: <https://skmtc.dev/matrix/apis/matrix-client-server-api/docs/_matrix/client/v3/register/available/get.ts> (a function with typed inputs; its response is checked against the schema)

Checks to see if a username is available, and valid, for the server.

The server should check to ensure that, at the time of the request, the
username requested is available for use. This includes verifying that an
application service has not claimed the username and that the username
fits the server's desired requirements (for example, a server could dictate
that it does not permit usernames with underscores).

Matrix clients may wish to use this API prior to attempting registration,
however the clients must also be aware that using this API does not normally
reserve the username. This can mean that the username becomes unavailable
between checking its availability and attempting to register it.

## Query parameters

- `username` string, required

## Response `200`

The username is available

- object
  - `available` boolean: A flag to indicate that the username is available. This should always be `true` when the server replies with 200 OK.

## Other responses

- `400`: Part of the request was invalid or the username is not available. This may include one of the following error codes: * `M_USER_IN_USE` : The desired username is already taken. * `M_INVALID_USERNAME` : The desired username is not a valid user name. * `M_EXCLUSIVE` : The desired username is in the exclusive namespace claimed by an application service.
- `429`: This request was rate-limited.

---

[API](https://skmtc.dev/matrix/apis/matrix-client-server-api.md) - [All operations](https://skmtc.dev/matrix/apis/matrix-client-server-api/llms.txt) - [OpenAPI document](https://skmtc.dev/matrix/apis/matrix-client-server-api/revisions/c7fe4072c681?raw)