Developer API — Business plan

WhatsApp Send API for Developers

Send WhatsApp messages from your CRM, store, or internal tools with a single HTTP call. Your own number, flat monthly pricing, no Meta business verification, no per-message fees.

Get your API key See Business plan pricing

API keys are created in the dashboard under API Keys (Business plan).

Authentication

All requests are authenticated with an API key in the Authorization header. Keys look like bwa_live_… and are shown once at creation — BulkWA stores only a hash.

Authorization: Bearer bwa_live_YOUR_KEY

Base URL: https://bulkwa-server.onrender.com. Keep keys server-side; never ship them in browser or mobile code. Revoke a leaked key instantly from the dashboard.

Send a message

POST/v1/messages

Field	Type	Description
to	string, required	Recipient phone in international format, e.g. `+14155550123`. 8-15 digits.
message	string, required	Text message body, max 4096 characters.
session_id	uuid, optional	Which of your WhatsApp numbers to send from. Defaults to your first connected session.

cURL

curl -X POST https://bulkwa-server.onrender.com/v1/messages \
  -H "Authorization: Bearer bwa_live_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "to": "+14155550123",
    "message": "Your order #1042 has shipped!"
  }'

Node.js

const res = await fetch("https://bulkwa-server.onrender.com/v1/messages", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.BULKWA_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    to: "+14155550123",
    message: "Your order #1042 has shipped!",
  }),
});

const data = await res.json();
// { id: "wamid...", status: "sent", to: "+14155550123" }

Response — 200

{
  "id": "3EB0538DA65B5B2F7A2B",
  "status": "sent",
  "to": "+14155550123"
}

API sends count against your plan’s message quota, are serialized with your campaigns’ anti-ban delays, and respect STOP opt-outs automatically. Text messages only for now — media support is planned for v1.1.

List your sessions

GET/v1/sessions

curl https://bulkwa-server.onrender.com/v1/sessions \
  -H "Authorization: Bearer bwa_live_YOUR_KEY"

Response — 200

{
  "sessions": [
    {
      "id": "0b6a1c9e-...",
      "phone_number": "+14155550100",
      "status": "connected"
    }
  ]
}

Check plan & usage

GET/v1/me

curl https://bulkwa-server.onrender.com/v1/me \
  -H "Authorization: Bearer bwa_live_YOUR_KEY"

Response — 200

{
  "plan": "business",
  "api_access": true,
  "usage": {
    "messages_sent_this_month": 1250,
    "monthly_limit": 10000,
    "remaining": 8750,
    "messages_sent_today": 84,
    "daily_limit": null
  }
}

Rate limits

60 requests per minute per account on every /v1 endpoint. Exceeding it returns 429.
Message sends also count against your plan’s monthly message quota — the same pool your dashboard campaigns use.
Sends through the same WhatsApp number are automatically spaced with anti-ban delays; bursts are queued, not dropped.

Error codes

Errors are JSON: { "error": "code", "message": "human explanation" }

Status	Code	Meaning
400	invalid_request / invalid_to	Malformed body — check that `to` has 8-15 digits and `message` is a non-empty string (max 4096 chars).
401	missing_api_key / invalid_api_key	No key, a malformed key, or a revoked key. Create a new key in the dashboard.
402	payment_locked	Your subscription payment failed. Update your payment method in Billing.
403	upgrade_required	The developer API requires the Business plan.
404	session_not_found	The session_id you passed does not belong to your account.
409	session_not_connected	No connected WhatsApp session. Reconnect in the dashboard and retry.
422	recipient_opted_out	This recipient replied STOP to you — BulkWA blocks the send for compliance.
429	quota_exceeded / rate limit	You hit your plan's message quota or the 60 requests/minute rate limit. Retry later.
502	send_failed	WhatsApp did not acknowledge the message. Safe to retry.
503	service_unavailable	Temporary backend issue (e.g. quota check failed). Retry with backoff.

Start sending in five minutes

Upgrade to the Business plan, connect your WhatsApp number by QR code, create a key, and make your first API call.

Create an API key View pricing