---
title: "Client ID"
source: https://dev.pageseeder.com/reference/glossary/client_id.html
last_updated: 2026-08-07T17:09:54+10:00
tokens: ~342
---

# Client ID

A unique identifier for an [OAuth client](oauth_client.md).

The Client ID is 64-bit random value assigned by PageSeeder when the client is registered.

> **Note:** It is also possible to set the Client ID. It might be necessary if an external app has already been configured with a specific Client ID such as when creating preconfigured environment or when migrating system.

The Client ID is a 16-character long hexadecimal number. To make it easier to read, it is generally formatted using uppercase letters and with a space every four characters.

For example: **3A5F ****4B16 ****873F ****7FA2**



### Client ID and internal ID

OAuth clients have two IDs assigned by PageSeeder when they are created:

- The *internal client ID* – is an immutable integer that PageSeeder assigns to all objects (members, groups, etc.)
- The *Client ID* – is a public mutable identifier defined by OAuth to uniquely identify apps in the context of OAuth.

Use the *internal ID* or the *Client ID (prefixed by ~)* when making the PageSeeder API with `{client}` URL parameter, for example `/ps/api/oauth/members/45/clients/123.json`. or `/ps/api/oauth/members/45/clients/~3a5f4b16873f7fa2.json`.

Use the *Client ID* in OAuth flows with the query parameter `client_id`, for example `client_id=3a5f4b16873f7fa2` (use the lower case format with no space in that case).