WhatsApp API for SaaS

Send WhatsApp messages
from your platform

REST API that connects your system to WhatsApp in minutes. Intelligent anti-ban, multi-tenant, signed webhooks. No Meta approval required.

Talk to sales See how it works
<5min
Integration time
3 lanes
Anti-ban priority
$20
per number/month
send-message.js
// Send a message with a single call
const response = await fetch('https://wa.sinapsia.com.ar/message/text', {
  method: 'POST',
  headers: {
    'apikey': 'your-api-key',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    instance: 'my_saas__client__main',
    to: '5491155551234',
    text: 'Hi! Your appointment is tomorrow at 10:00',
    lane: 'normal'
  })
})
Response 200 OK { "queued": true, "id": "msg_a1b2c3", "lane": "normal", "eta": "~5s" }
Message delivered
Anti-ban active
Webhook sent
Intelligent anti-ban Multi-tenant Webhooks HMAC-SHA256 QR & Pairing Code Text, image, audio, video Multi-number round-robin Spintax 3 priority lanes No Meta approval REST API Intelligent anti-ban Multi-tenant Webhooks HMAC-SHA256 QR & Pairing Code Text, image, audio, video Multi-number round-robin Spintax 3 priority lanes No Meta approval REST API
See it in action

Your platform sends.
WhatsApp delivers.

One POST to our API and your message reaches the end user's WhatsApp with anti-ban, random delay and confirmation via webhook.

Health+ Clinic
online
Today
Hi Maria! Reminder: your appointment tomorrow at 10:00 with Dr. Lopez. 09:15
Perfect, I'll be there!
We're sending the preparation instructions:09:16
Study-Preparation.pdf
1 page - PDF
Today
Your order #4521 has been shipped! Arrives today between 14:00 and 18:00. 11:30
Great! Is there tracking?
Yes! Track your shipment here: https://track.mystore.com/4521 11:31
Thanks!!
Today
Hey John! Your 7pm CrossFit class has 2 spots left. Confirming? 17:00
Yes, confirmed!
Done! Reserved. Don't forget to bring a towel and water. 17:01
Today
Hi Laura! We have a new listing matching your search: 2-bed in downtown, USD 85,000. 10:20
Interested! Can I visit it?
Of course! We have availability tomorrow at 11:00 or 16:00. Which works for you? 10:22
11am is perfect

Anti-ban with 3 lanes

Urgent (1-2s), Normal (3-8s), Bulk (8-15s). Random delays, hourly and daily limits. Your number protected.

Text, image, audio, video, PDF

All message types from a single endpoint. With spintax for automatic variations.

Real-time webhooks

Receive delivery, read and incoming message events. Signed with HMAC-SHA256.

Integrations

Connect with your stack. No extra code.

Standard REST API. If your tool can make HTTP requests, you can already send WhatsApp messages.

n8n
HTTP Request node
Make
HTTP module
Zapier
Webhooks
Power Automate
HTTP connector
Retool
REST datasource
AI Agents
Tool / function calling
Your backend
Any language
Pipedream
HTTP step
Home Assistant
REST command
Example: n8n workflow
New CRM lead
Personalize message
SinapsIA Connect
// HTTP Request node in n8n
Method: POST
URL: https://wa.sinapsia.com.ar/message/text
Headers: { "apikey": "{{ $credentials.sinapsiaKey }}" }
Body: {
  "instance": "my_saas__support__main",
  "to": "{{ $json.phone }}",
  "text": "Hi {{ $json.name }}! Thanks for your inquiry.",
  "lane": "normal"
}
One HTTP Request is all you need
How it works

Three steps. Minutes.

No Meta approval, no templates, no Business API needed. Link a number and start sending.

01

Get your API key

Contact us, we create your tenant and send you your API key. Ready to integrate.

apikey: 'sk_live_your_api_key'
02

Link a number

Your user scans a QR code or enters a pairing code. The session connects instantly.

POST /instance/create
GET  /instance/{name}/qr
03

Send and receive

POST to the message endpoint. The gateway queues, applies anti-ban and sends. You receive confirmation via webhook.

POST /message/text
{ to: "1555...", text: "Hello!" }
Use cases

Any SaaS that needs
WhatsApp.

If your platform has users expecting notifications, reminders or conversations via WhatsApp, SinapsIA Connect is for you.

Customer support

Support via WhatsApp. Helpdesk connected to your CRM. Fast responses with no wait queue.

1-5 numbersConversationalLow risk

Transactional notifications

Appointment, shipping, payment confirmations. Each message to a different customer, low risk.

Hundreds/dayAutomatedExpected

Conversational AI agents

Chatbot that responds when the user initiates. Low volume, maximum quality.

1-2 numbersUser initiatesMinimal risk

Internal automations

Monitoring alerts, team notifications. Internal recipients only, zero risk.

Few messagesInternalZero risk

What it is NOT designed for

Not viable or recommended for these cases:

Mass marketing

Promotions to lists of 500+ contacts without consent. High ban risk.

Use Email or SMS

Hundreds of numbers

Scaling to 100+ numbers on a datacenter server. WhatsApp detects the spam pattern.

Requires proxies

Enterprise / Compliance

Approved templates, blue tick, SLA. Requires Meta's official WhatsApp Cloud API.

Use Business API

Spam / Unsolicited

Messages to contacts who did not consent. No system protects against this.

Be ethical
Features

Everything your SaaS needs

Robust infrastructure so you don't waste time reinventing the WhatsApp wheel.

Intelligent anti-ban
3 lanes with random delays, hourly/daily limits, automatic pause on rate-limit. Urgent never waits.
Core feature
Isolated multi-tenant
Each SaaS with its own API key, instances and data. Full logical isolation via naming convention.
Full multimedia
Text, image with caption, audio as voice note, video and PDF documents. All from a unified endpoint.
Signed webhooks
Delivery, read and incoming message events. HMAC-SHA256 on every request. Automatic retries.
QR & Pairing Code
No Meta approval. Your user scans a QR or enters an 8-digit code and gets linked instantly.
Round-robin
Automatically distributes messages across multiple numbers. Balances load and protects each line.
Frequently asked questions

Questions? Here are the answers.



No. This is not Meta's official Business API. You don't need approved templates or a verification process. Link a number and start sending immediately.
Our anti-ban system significantly reduces risk with random delays, hourly/daily limits and automatic pauses. We don't recommend bulk sends to contacts who don't know you.
Minutes. It's a standard REST API with JSON. We have documentation with examples in curl, JavaScript and Python.
Yes. Each incoming message triggers a webhook to your configured URL, signed with HMAC-SHA256 so you can verify authenticity.
Yes. We support text, images with caption, audio (as voice note), video and PDF documents. All from a single endpoint with anti-ban included.
There is no technical limit. But the risk depends on the use case: helpdesk/notifications to contacts expecting the message = low risk, even with hundreds/day. Mass marketing to cold contacts = high risk at any volume. We recommend contacting us to evaluate your case.
It depends on the use case. Customer support and notifications carry very low risk because the user expected the message. Mass marketing to contacts without consent carries high risk. See the "Not designed for" section for details.
Meta's official API targets enterprise ($0.03-0.06 per message, approved templates, guaranteed SLA). SinapsIA is more affordable for SMBs and SaaS. Advantage: native anti-ban, setup in minutes. Disadvantage: no SLA or ban appeal process.
No technical limit. We recommend starting with 1-5 numbers. If you need to scale to more, contact us to discuss the best solution for your case.
Completely. Each tenant has their own API key and can only access their own instances. Isolation is enforced via naming convention and auth middleware.

Integrate WhatsApp today

Start with the Starter plan and scale when you need it. No contracts, no approvals.

Connect now