The difference between openid and unionid
OpenID: The identification of ordinary users, unique to the current developer account. An openid corresponds to an official account.
UnionID: User unified ID. For applications under a WeChat open platform account, the unionid of the same user is unique.
Developers can obtain basic user information through OpenID. In particular, if the developer has multiple mobile applications, website applications and public accounts, the uniqueness of the user can be distinguished by obtaining the unionid in the user’s basic information, because as long as the mobile application under the same WeChat open platform account , website application and public account, the user’s unionid is unique. In other words, for the same user, the unionid is the same for different applications under the same WeChat open platform
![What is the difference between WeChat openid and unionid?1 WeChat Development](https://www.infocodecn.com/wp-content/themes/justnews/themer/assets/images/lazy.png)
For the same user, the UnionID is the same for different applications under the same WeChat open platform account. “In the previous OpenID mechanism, each WeChat account had only a unique OpenID for each official account, so different WeChat official accounts could not share users. Now with UnionID, it is enough.
For users, a WeChat account can be used to log in to official accounts, mobile applications and PC websites across platforms at the same time, without re-registration, which is convenient and fast.
For developers:
1. It can reduce user registration cost, improve user retention rate, and better manage user information.
2. If it is a PC website, the WeChat login is the same as we log in to the web version of WeChat on the PC, just scan the QR code directly, which greatly facilitates the user and ensures safety.
3. When the same user uses the same WeChat to log in to the PC website, mobile application, and official account at the same time, the data of these three parties can be stored uniformly. No matter which end the user operates on, the three major platforms will uniformly modify the results, which will be very convenient. Data management and behavior statistics for the same user.
For more information on WeChat development, please contact Shanghai Official Account Development Company New Mileage Customer Service