Send Messages

Send text or media to a single WhatsApp user, group, or channel.

Request Body

{
  "instance_id": "string",          // Your instance identifier
  "access_token": "string",         // API access token
  "chatId": "string",               // Recipient identifier (see formats below)
  "text": "Hello world!",           // Optional. Message text
  "file": {                          // Optional. Media payload
    "data": "base64string",         // OR
    "url": "https://example.com/photo.jpg"
  },
  "reply_to": "false_111...AAAA"    // Optional. ID of the message you are replying to
}

Field Descriptions

Field	Type	Required	Description
`instance_id`	string	✔️	Your unique instance identifier.
`access_token`	string	✔️	Secret token generated for the instance.
`chatId`	string	✔️	Recipient address. See Chat ID Formats.
`text`	string	❌	Plain‑text body of the message. Omit when sending media‑only messages.
`file.data`	string (base64)	❌	Base64‑encoded media payload. Provide either `file.data` or `file.url`.
`file.url`	string (URL)	❌	HTTPS URL to a publicly accessible file.
`reply_to`	string	❌	ID of the message you wish to reply to.

Chat ID Formats

Context	Example	Notes
User	`12132132131@c.us`	International phone number (E.164) without the leading `+`, suffixed with `@c.us`.
Group	`12312312123133@g.us`	Group IDs end with `@g.us`.
Hidden user	`123123123@lid`	Internal user ID introduced with Communities.
Channel	`123123123@newsletter`	WhatsApp Channels (📰).

Sending Media (`file`)

You can attach media in one of two mutually exclusive ways:

Inline Base64

"file": {
  "data": "iVBORw0KGgoAAA..."
}

Remote URL

"file": {
  "url": "https://cdn.example.com/banner.jpg"
}

Note: The URL must be publicly reachable by the API server.

Replying to a Message

Include the reply_to field to create a threaded reply:

"reply_to": "false_11111111111@c.us_AAAAAAAAAAAAAAAAAAAA"

Example – Send an Image

{
  "instance_id": "123456789",
  "access_token": "123456789",
  "chatId": "12132132130@c.us",
  "file": {
    "url": "https://example.com/photo.jpg"
  },
  "reply_to": "false_12132132130@c.us_BBBBBBBBBBBBBBBBBBBB"
}

Success Response

{
  "result": true,
  "message_id": "true_12132132130@c.us_CCCCCCCCCCCCCCCCCCCC"
}

Additional Notes

Every call consumes one send‑message quota unit.

Audio files with .mp3 or .ogg extensions are treated as voice notes.

The maximum file size is 64 MB.

Request Body#

Field Descriptions#

Chat ID Formats#

Sending Media (file)#

Replying to a Message#

Example – Send an Image#

Success Response#

Additional Notes#