Send WhatsApp messages from your app

Before you start

1. 1 Start a free trial with your email: your API key arrives in your inbox (3 days, no card).
2. 2 Open the portal link from that email, go to Connect Device and scan the QR code from WhatsApp → Linked devices.
3. 3 Keep your API key secret, like a password: send it in the Authorization header, never in a public web page.

Send a text message

Send a POST request to https://wabot.astranexo.com/api/send-message with your key as a Bearer token:

curl -X POST https://wabot.astranexo.com/api/send-message \
  -H "Authorization: Bearer $WABOT_KEY" \
  -H "Content-Type: application/json" \
  -d '{"to": "50688887777", "message": "Your order #1001 ships today"}'

• to: the recipient's number with its country code (8 to 20 characters; +, spaces, dashes and parentheses are fine).
• message: the text, up to 4,096 characters. Emoji and line breaks work.
• idempotency_key (optional): your own ID for the message. Sending again with the same key returns the first message instead of sending twice, so retries are safe.

WaBot answers right away and queues the message:

{
  "success": true,
  "message": "Message queued successfully",
  "message_id": 123,
  "status": "queued",
  "queue_position": 1,
  "estimated_wait_seconds": 0,
  "remaining_today": null
}

Send an image, video or document

Use /api/send-media with a public link to the file. WaBot downloads it and sends it from your number, with an optional caption:

curl -X POST https://wabot.astranexo.com/api/send-media \
  -H "Authorization: Bearer $WABOT_KEY" \
  -H "Content-Type: application/json" \
  -d '{"to": "50688887777", "file_url": "https://example.com/invoice-1001.pdf", "caption": "Invoice #1001"}'

• Images: JPG, PNG, GIF, WebP. Video: MP4, 3GP. Documents: PDF, Word, Excel, PowerPoint. Audio: MP3, OGG, WAV.
• Up to 16 MB, from a link anyone can open.

Check that it went out

Every send returns a message_id. Ask for its status:

curl https://wabot.astranexo.com/api/message/123/status \
  -H "Authorization: Bearer $WABOT_KEY"

The status goes queued → sending → sent, or failed with the reason in error. sent means WhatsApp accepted the message from your number.

Examples in your language

JavaScript (Node.js 18+, ES module)

const response = await fetch('https://wabot.astranexo.com/api/send-message', {
  method: 'POST',
  headers: {
    Authorization: `Bearer ${process.env.WABOT_KEY}`,
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({ to: '50688887777', message: 'Your appointment is tomorrow at 9:00' }),
});
console.log(await response.json());

Python

import os, requests

response = requests.post(
    'https://wabot.astranexo.com/api/send-message',
    headers={'Authorization': f"Bearer {os.environ['WABOT_KEY']}"},
    json={'to': '50688887777', 'message': 'Your appointment is tomorrow at 9:00'},
)
print(response.json())

PHP (Laravel)

use Illuminate\Support\Facades\Http;

$response = Http::withToken(config('services.wabot.key'))
    ->post('https://wabot.astranexo.com/api/send-message', [
        'to' => '50688887777',
        'message' => 'Your appointment is tomorrow at 9:00',
    ]);

$messageId = $response->json('message_id');

Send from Google Sheets

In your sheet, open Extensions → Apps Script and paste this function. Save your API key under Project Settings → Script properties as WABOT_KEY, so it isn't in the code:

function sendWhatsApp(to, message) {
  const key = PropertiesService.getScriptProperties().getProperty('WABOT_KEY');
  const response = UrlFetchApp.fetch('https://wabot.astranexo.com/api/send-message', {
    method: 'post',
    contentType: 'application/json',
    headers: { Authorization: 'Bearer ' + key },
    payload: JSON.stringify({ to: String(to), message: message }),
    muteHttpExceptions: true,
  });
  return JSON.parse(response.getContentText());
}

Call it from your own script, for example in a loop over the rows of your sheet. WaBot spaces the sends for you.

Zapier and Make

No code needed: in Zapier use Webhooks by Zapier, and in Make use the HTTP module. Send a POST to https://wabot.astranexo.com/api/send-message with the header Authorization: Bearer plus your key, and a JSON body with to and message, the same as the examples above.

Limits and good practice

• Messages from your number go out one at a time, at least 5 seconds apart (up to 10 per minute), to stay within WhatsApp's guidelines. You can queue them all at once; WaBot does the spacing.
• The free trial includes 50 messages in total. Paid plans have no daily cap.
• If your phone disconnects, messages wait up to 24 hours and go out when you link it again.
• The API sends; it doesn't notify you of incoming messages. To read and answer chats, connect Claude or ChatGPT.
• WaBot is not Meta's official WhatsApp Business API: it links your number the way WhatsApp Web does. Use it for messages people expect, not bulk or unsolicited messages.

Which plan do I need?

To message customers or anyone else, choose Unlimited ($6/month or $60/year), documents included. Personal ($1/month or $10/year) sends text, images and video to your own number only, which suits alerts and reminders to yourself. Compare plans.

If something goes wrong

• 401: the API key is missing or wrong.
• 403 with "reason": "plan_expired": your trial or plan ended. The response includes an upgrade_url to subscribe; your key stays the same.
• 422: a field is missing or invalid (for example, a number that is too short).
• 403 with "reason": "trial_limit": the free trial's 50 messages are used up. The response includes an upgrade_url to subscribe; your key stays the same.
• 429: you're sending too fast. Wait the seconds in retry_after and try again.