Last updated: 2020-05-14 14:05:45


Product Introduction

Tencent is the earliest and biggest instant messaging developer in China. QQ and WeChat, both developed by Tencent, have become indispensable apps for every Internet user. In conformity with the trend of industrial digital transformation, Tencent now shares its high-concurrency and highly reliable instant messaging capabilities. With SDKs provided by Tencent, you can easily integrate instant messaging features into your apps to meet various business needs.
For developer requirements and scenarios in different phases, the Instant Messaging (IM) team provides a series of solutions, including the Android, iOS, Windows, and web SDK components, as well as capabilities for integrating RESTful APIs and Third-Party Callback APIs on the server. With these components and capabilities, developers can construct reliable and stable IM products for free and global communication.


IM features a comprehensive suite of solutions including global access, one-to-one chat, group chat, message push, profile and relationship chain hosting, and account authentication. It also provides complete app access and backend management APIs.


Access service

The access service provides IM with highly interconnected, reliable, and secure global network connection channels and proprietary multi-level optimal addressing algorithms to implement scheduling across private and public networks. Technologies including intelligent compatibility for passing through gateway policies, persistent connection multiplexing, transport-layer protocol optimization, and channel encryption allow businesses to establish simple and reliable communication with business backends without concerns about network details.

One-to-one chat

One-to-one chat supports various message types including text, emojis, locations, images, audio, short video, and custom message. It provides special features such as red packets, chatbots, read receipt, and message recall as well as services such as offline messages and roaming messages. For more information, see One-to-One Messages.

Group chat

A group chat involves multiple participants. IM provides five built-in group types, including private group (private), public group (public), chat room (ChatRoom), audio-video chat room (AVChatRoom), and broadcasting chat room (BChatRoom). These group types are tailored to different group communication scenarios.

  1. Private group: this group type is suitable for private chat scenarios, where group information is not made public and users can only join the group through invitation by an existing group member. It’s similar to a WeChat group.
  2. Public group: this group type is suitable for public chat scenarios and has a strict management and admission mechanism. It’s similar to a QQ group.
  3. Chat room: this group type has a less stringent management mechanism and allows users to join and exit the room freely. In addition, members can view the messages sent before they joined the chat room.
  4. Audio-video chat room: this group type is similar to a chat room, but it does not impose a limit on the number of room members. It allows users to receive messages as guests on web clients.
  5. Broadcasting chat room: this group type does not impose a limit on the number of room members and allows users to receive messages as guests on web clients. It is suitable for scenarios where messages need to be pushed to all online members on the app.

Groups are highly customizable, allowing you to use custom group types, fields, group IDs, and event callbacks. You can fully customize your group based on the needs of your app. For more information, see Group System.

While audio-video chat rooms (AVChatRoom) and broadcasting chat rooms (BChatRoom) support unlimited group members, if a spike in group members is expected within a short time (in scenarios such as large online events where members in a single group exceed 50,000), contact Tencent Cloud customer service or sales representatives in advance and report service resource usage by providing the SDKAppID and the scheduled event time.

Profile and relationship chain hosting

IM provides a holistic solution for profile and relationship chain management, storing user profiles (for example, nicknames, profile photos, and custom profile fields), friend lists, blacklists, and other information. IM's profile and relationship chain hosting service provides a backup service with up to 12 copies and multi-data center remote deployment to improve service quality and disaster recovery performance. For more information, see Profile Management and Relationship Chain Management.

Account authentication

Data security is ensured with asymmetric encryption ECDSA-SHA256 and hash encryption HMAC-SHA256 (HMAC-SHA256 is recommended). Developers can directly use the app’s own account to quickly integrate IM services, freeing themselves from tedious account mapping work. With simple SDK integration and convenient API calls, it is easy to authenticate user accounts (UserID) and passwords (UserSig). For more information, see Login Authentication.

Management and Monitoring

In addition to basic instant messaging features, IM provides a convenient and easy-to-use console, which allows you to create apps, download IM SDKs, query app configurations, perform joint app testing, and integrate instant messaging capabilities. IM Console also supports various features such as backend message delivery, user management, group management, and statistics. For more information, see Console Guide.

Advanced Features


RESTful APIs are HTTP management APIs that provide the app backend with a management entry at the backend. For the list of RESTful APIs currently supported by IM, see RESTful API Overview.

In addition to RESTful APIs, IM Console also provides simple features such as data management and one-to-one and one-to-many messaging. Developers can manage, view, and test data in IM Console. In contrast, RESTful APIs are less user-friendly, but they can provide more powerful management capabilities.

Third-party callbacks

When IM initiates a third-party callback, it sends requests to the app backend before or after an event. Then, the app backend synchronizes data accordingly or intervenes in the subsequent processing of the event.
IM provides a diverse set of callback APIs, which are free of charge. For more information, see the List of Callback Commands.