What is the format of a phone number in WhatsApp's jid?

[jakiyasultana2525]

In WhatsApp’s internal database structure, particularly in the `wa.db` SQLite database file, the **JID** (Jabber ID) is used as a unique identifier for each contact and chat participant. This JID is essential to how WhatsApp manages communications, and it directly incorporates the **phone number** of the contact. The format of a phone number in WhatsApp’s JID is both standardized and predictable, adhering to a convention derived from the XMPP protocol, upon which WhatsApp’s architecture is loosely based.

The standard format of a JID for individual users is:
**`[phone_number]@s.whatsapp.net`**

Here’s a breakdown of this format:

* **`[phone_number]`**: This is the actual mobile number of the user, stripped of any formatting such as spaces, dashes, parentheses, or plus signs. However, it does include the full **international country code**. For example, a U.S. number like +1 (234) 567-8900 would be formatted in the JID as `12345678900`.
* **`@s.whatsapp.net`**: This domain-like suffix is used internally stockholder data by WhatsApp to distinguish standard single-user accounts. The `s` stands for "subscriber," and the `whatsapp.net` part reflects the service’s server namespace.

For example, a contact with phone number `+447911123456` (UK number) would have the JID:
**`[email protected]`**

This format is **not user-visible** within the app but is extensively used internally and stored in tables like `wa_contacts` and `messages` within WhatsApp’s database files (`wa.db` and `msgstore.db`). In these tables, each contact’s JID acts as the primary reference key for linking messages, status updates, and other user information.

In the case of group chats, the JID format changes slightly:

* Group JIDs look like this: **`[creator_phone_number]-[timestamp]@g.us`**
* For example: `[email protected]`

This distinguishes group chats from individual user accounts. The suffix `@g.us` designates a group, while the creator’s phone number and a Unix timestamp make each group ID unique.

It’s also worth noting that WhatsApp Business accounts follow the same JID format (`[number]@s.whatsapp.net`), though certain business features may associate metadata via other systems not evident in the local databases.

The consistent use of the JID format enables WhatsApp to easily match messages to senders and recipients, maintain user identity across devices, and manage group memberships. It also supports WhatsApp’s encrypted messaging structure, where keys and sessions are bound to these identifiers.

In conclusion, WhatsApp stores phone numbers in JIDs using a clean international number format (digits only, including country code), followed by `@s.whatsapp.net` for individuals or `@g.us` for groups. This standardized structure allows efficient identity management and message routing within the app’s encrypted, decentralized messaging framework.