Send Audio Message

Send audio messages that appear as voice notes in WhatsApp. These are different from regular audio files and display as playable voice messages (PTT - Push-to-Talk) in the chat.

Endpoint

POST /message/sendWhatsAppAudio/:instanceName

Path Parameters

instanceName

string

required

The name of your WhatsApp instance that you created

Request Body

This endpoint supports three methods for sending audio:

URL: Provide a direct link to the audio file
Base64: Provide the base64-encoded audio content
File Upload: Use multipart/form-data to upload an audio file

number

string

required

The recipient’s WhatsApp number in international format (without + symbol)Example: 5511999999999 for a Brazilian number

audio

string

required

The audio content as a URL or base64 string (not required when using file upload)Examples:

URL: https://example.com/audio.mp3
Base64: data:audio/mpeg;base64,SUQzBAAAAAAAI1RTU0UAAAA...

delay

integer

Delay before sending the message in millisecondsExample: 1000 for 1 second delay

quoted

object

Quote a previous message by providing its key and message object

encoding

boolean

Enable audio encoding for better compatibilityDefault: false

Response

key

object

Message key information

message

object

The sent message object containing the audio message data

messageTimestamp

string

Unix timestamp when the message was sent

status

string

Message status (e.g., “PENDING”, “SENT”)

Code Examples

curl -X POST https://your-api-url.com/message/sendWhatsAppAudio/my-instance \
  -H "Content-Type: application/json" \
  -H "apikey: YOUR_API_KEY" \
  -d '{
    "number": "5511999999999",
    "audio": "https://example.com/voice-note.mp3"
  }'

Advanced Examples

Send audio from URL

{
  "number": "5511999999999",
  "audio": "https://example.com/voice-message.mp3"
}

Send audio with base64 encoding

{
  "number": "5511999999999",
  "audio": "data:audio/mpeg;base64,SUQzBAAAAAAAI1RTU0UAAAA...",
  "encoding": true
}

Send audio as reply to message

{
  "number": "5511999999999",
  "audio": "https://example.com/voice-note.mp3",
  "quoted": {
    "key": {
      "id": "BAE5F2D3E4F5A6B7",
      "remoteJid": "[email protected]",
      "fromMe": false
    },
    "message": {
      "conversation": "Original message"
    }
  }
}

Audio Format Guidelines

For best compatibility with WhatsApp voice messages, use the following formats:

Recommended Formats

Format: MP3, OGG (Opus codec), AAC
Sample rate: 16kHz or 48kHz
Bitrate: 64kbps - 128kbps
Channels: Mono (1 channel)
Maximum duration: No hard limit, but shorter is better for voice notes
Maximum size: 16MB

Supported Audio Formats

MP3 (audio/mpeg)
OGG with Opus codec (audio/ogg)
M4A/AAC (audio/mp4, audio/aac)
WAV (audio/wav) - will be converted

Audio files sent via this endpoint will appear as voice messages (PTT) in WhatsApp, displayed with a play button and waveform. To send regular audio files as documents, use the Send Media endpoint with mediatype: "audio".

PTT vs Regular Audio

Voice Message (PTT) - This Endpoint

Appears as a voice message with waveform
Plays automatically in sequence
Designed for quick voice communication
Maximum 16MB file size

Regular Audio File - Send Media Endpoint

Appears as an audio file attachment
Requires manual play
Suitable for music, podcasts, etc.
Can be larger files

Error Responses

status

number

HTTP status code

message

string

Error description

Common Errors

Status Code	Error Message	Solution
400	”Owned media must be a url, base64, or valid file with buffer”	Ensure audio is provided as URL, base64, or file upload
401	Unauthorized	Check your API key
404	Not Found	Verify instance exists and is connected
500	Internal Server Error	Check audio file format and size

The audio URL must be publicly accessible. If you’re getting errors, verify that the URL can be accessed without authentication.

Overview

Instance Management

Messaging

Chats

Groups

Contacts

Labels

Settings

Proxy

Send Audio Message