> ## Documentation Index
> Fetch the complete documentation index at: https://docs.social-api.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Zalo

> Connect a Zalo Official Account to send and receive direct messages and publish articles and videos through SocialAPI.

A Zalo Official Account (OA) is the business-facing account type on Zalo, Vietnam's dominant messaging app. The Zalo connector authenticates an OA through OAuth 2.0 with PKCE, and OAuth is provided by SocialAPI.ai: you don't register your own Zalo app.

## At a glance

| Field         | Value                                                                     |
| ------------- | ------------------------------------------------------------------------- |
| Platform slug | `zalo`                                                                    |
| Auth type     | OAuth 2.0 with PKCE                                                       |
| API           | Zalo Official Account Open API                                            |
| Best for      | A unified inbox and article/video publishing for a Zalo Official Account. |

## Capabilities

| Feature              | Supported | Notes                                                           |
| -------------------- | --------- | --------------------------------------------------------------- |
| Receive and send DMs | Yes       | Customer service messaging, subject to the 7-day window below   |
| Publish articles     | Yes       | Text articles, created asynchronously (see below)               |
| Publish videos       | Yes       |                                                                 |
| Update posts         | Yes       |                                                                 |
| Delete posts         | Yes       |                                                                 |
| Webhooks             | Yes       | Inbound events are verified with an `X-ZEvent-Signature` header |
| Comments             | No        | Zalo has no public API for comments                             |
| Reviews              | No        | Zalo has no public API for reviews                              |
| Mentions             | No        | Zalo has no public API for mentions                             |

Comments, reviews, and mentions aren't planned as "coming soon": Zalo simply doesn't expose a public API for any of the three, so SocialAPI has nothing to connect to.

## Connecting

Zalo uses OAuth 2.0 with PKCE (Proof Key for Code Exchange). Start the connection through the standard connect flow with `platform=zalo`; SocialAPI generates the PKCE verifier and challenge, sends the user to Zalo's authorization screen, and completes the code exchange on the callback.

Each Zalo OAuth token is scoped to exactly one Official Account: listing accounts after connecting always returns a single account, the OA that authorized.

### Redirect URI domain verification

Zalo requires the callback domain to be **both** registered as the app's callback URL **and** domain-verified in the Zalo portal, using DNS TXT, an HTML file, or a meta tag. Registering the callback URL alone is not enough: Zalo rejects the authorization request with "invalid redirect uri" until the domain is also verified. Complete both steps in the Zalo portal before connecting an account.

### Token lifetime

Access tokens last about 25 hours. Refresh tokens last 3 months and are single-use: Zalo issues a new refresh token every time the current one is used, and the old one stops working. SocialAPI.ai handles this rotation automatically, so you never see or manage a refresh token directly.

## The 7-day messaging window

Zalo only lets an Official Account send a customer service message to a user who has interacted with the OA within the last **7 days**. Messages sent inside the first **48 hours** of that window are free; messages sent after 48 hours but within 7 days may incur a cost on Zalo's side. Sending outside the 7-day window is rejected and surfaces to you as an **HTTP 422**.

## Publishing articles and videos

Zalo Official Accounts publish articles (and video posts) rather than short-form posts. Article creation is **asynchronous**: after you submit a draft, SocialAPI polls Zalo's verification endpoint until the article finishes processing and returns its final ID. See [Zalo publishing](/posts/zalo) for the full request and response shapes, including the `title` requirement enforced before an article can be submitted.

## Related

* [Zalo publishing](/posts/zalo)
* [Platform support](/guides/platforms)
* [Inbox](/guides/inbox)
* [Errors](/guides/errors)