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WhatsApp REST API

WhatsApp REST API – User Guide WhatsApp REST API allows you to connect your applications, websites, or systems directly to your WhatsApp account for programmatic messaging. It enab...

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WhatsApp REST API – User Guide

WhatsApp REST API allows you to connect your applications, websites, or systems directly to your WhatsApp account for programmatic messaging.

It enables you to send messages automatically, build integrations, and create custom workflows beyond the dashboard.

Overview

With WhatsApp REST API, you can:

  • Send messages from external systems
  • Connect CRM, websites, or SaaS platforms
  • Trigger automated messaging via API
  • Manage multiple WhatsApp accounts
  • Generate QR codes and manage instances
  • Build custom automation workflows

This module is designed for developers and advanced business integrations.

How to Access

Go to:

WhatsApp Unofficial → REST API

Requirements

Before using this feature, ensure:

  • The REST API feature is enabled in your plan
  • WhatsApp Unofficial server is installed and running
  • At least one WhatsApp account is connected
  • WhatsApp API configuration is enabled
  • The WhatsApp Server URL is correctly configured

If the server or account is not configured, API requests may fail.

Main Purpose

REST API enables system-to-system communication.

Use it to:

  • Send messages from your own software
  • Connect WhatsApp to forms or CRM systems
  • Trigger messages from system events
  • Send transactional notifications
  • Build custom integrations or SaaS features

Workflow

Typical setup process:

  1. Open REST API
  2. Create or select a WhatsApp instance
  3. Generate QR code
  4. Connect WhatsApp account
  5. Copy access token
  6. Send API requests from your system

Key Components

1. Access Token

Used to authenticate API requests.

  • Required for every API call
  • Must be kept secure
  • Should never be exposed publicly

2. WhatsApp Account

Select which account will be used for sending.

Useful when managing multiple numbers.

3. Instance ID

Each connection uses an Instance ID.

Used to:

  • Identify the WhatsApp session
  • Reconnect accounts
  • Manage instances

4. QR Code Connection

If not connected:

  1. Generate QR code
  2. Scan with WhatsApp
  3. Wait until status becomes connected

Once connected, the API is ready to use.

5. Webhook

Webhook allows your system to receive events.

Used for:

  • Incoming message notifications
  • Delivery updates
  • Session status changes
  • System synchronization

Common Use Cases

Website Forms

Send WhatsApp messages when users submit forms.

CRM Integration

Trigger messages when leads are created or updated.

Order Notifications

Send confirmations, reminders, or delivery updates.

SaaS Automation

Build automated messaging workflows inside your system.

Internal Alerts

Send notifications from internal tools or systems.

API Controls

Depending on your setup, you may see:

  • Generate Instance ID
  • Get QR Code
  • Save Webhook
  • Reconnect
  • Reboot
  • Reset

These help manage WhatsApp sessions directly.

Best Practices

To ensure stability:

  • Use only connected accounts
  • Protect access tokens
  • Avoid sending messages too quickly
  • Validate webhook URLs
  • Monitor delivery using Reports
  • Reconnect sessions if needed

Security Guidelines

Because this is an API feature:

  • Never expose your access token
  • Store credentials securely
  • Restrict API access
  • Rotate tokens periodically
  • Use HTTPS in production

Troubleshooting

API Not Sending Messages

Possible causes:

  • Account disconnected
  • Invalid access token
  • Incorrect server URL
  • Instance not connected
  • WhatsApp server offline

QR Code Issues

Possible causes:

  • Scan not completed
  • Session not established
  • Server configuration error
  • Connection delay

Webhook Not Working

Possible causes:

  • Invalid or unreachable URL
  • Route blocked
  • Domain mismatch
  • SSL or firewall issue

Reconnect Fails

Possible causes:

  • Session expired
  • Invalid instance ID
  • Server offline
  • Requires new QR login

Recommended Workflow

Follow this process:

  1. Configure WhatsApp Server URL
  2. Enable REST API
  3. Generate Instance ID
  4. Connect account via QR
  5. Confirm connection
  6. Configure webhook (optional)
  7. Use access token in your system
  8. Send test API request
  9. Monitor results in Reports

Related Modules

Works together with:

  • Profile Info – verify connection status
  • Reports – monitor API activity
  • Live Chat – handle incoming conversations
  • Contacts – manage recipients
  • Bulk Campaigns – large-scale sending
  • AI Smart Reply, Auto Reply, Chatbot – combine API with automation

Final Note

WhatsApp REST API is the most powerful way to extend WhatsApp beyond the dashboard.

Use it to build integrations, automate messaging, and create scalable communication systems.