API Documentation

Integrate InstaInvoice into your applications with our REST API. Perfect for building custom workflows and automations.

API Access - Pro Feature

API access is available exclusively for Pro subscribers. Upgrade to unlock programmatic access to your invoicing data.

Upgrade to Pro

PGK 100

per month

Secure Authentication

API keys are encrypted and can be regenerated anytime from your dashboard

RESTful Design

Standard HTTP methods and JSON responses for easy integration

Real-time Data

Access up-to-date invoice, client, and payment information instantly

Getting Started

Base URL

https://api.instainvoice.com/v1

Authentication

All API requests require authentication using your API key. Include it in the Authorization header:

Authorization: Bearer your_api_key_here

Security Note

Never expose your API key in client-side code. Always make API calls from your server.

Rate Limits

Free Tier

100

requests per hour

Pro Tier

5,000

requests per hour

API Endpoints

GET/api/v1/invoices

List all invoices

Response:

{
  "data": [
    {
      "id": "inv_123",
      "invoice_number": "INV-2024-001",
      "client": {
        "id": "client_456",
        "name": "Acme Corp"
      },
      "amount": 5000.00,
      "status": "paid",
      "created_at": "2024-03-15T10:30:00Z"
    }
  ],
  "pagination": {
    "page": 1,
    "per_page": 50,
    "total": 100
  }
}

POST/api/v1/invoices

Create a new invoice

Request Body:

{
  "client_id": "client_456",
  "invoice_date": "2024-03-20",
  "due_date": "2024-04-20",
  "items": [
    {
      "description": "Web Development",
      "quantity": 40,
      "unit_price": 125.00
    }
  ],
  "tax_rate": 10.0,
  "notes": "Payment due within 30 days"
}

Response:

{
  "id": "inv_789",
  "invoice_number": "INV-2024-002",
  "status": "draft",
  "total": 5500.00,
  "created_at": "2024-03-20T14:15:00Z"
}

GET/api/v1/clients

List all clients

Response:

{
  "data": [
    {
      "id": "client_456",
      "name": "Acme Corp",
      "email": "[email protected]",
      "total_invoices": 12,
      "outstanding_balance": 2500.00
    }
  ]
}

POST/api/v1/payments

Record a payment

Request Body:

{
  "invoice_id": "inv_123",
  "amount": 5000.00,
  "payment_date": "2024-03-25",
  "payment_method": "bank_transfer",
  "notes": "Received via BSP transfer"
}

Response:

{
  "id": "payment_321",
  "invoice_id": "inv_123",
  "amount": 5000.00,
  "status": "completed",
  "created_at": "2024-03-25T09:00:00Z"
}

Use Cases

Automated Invoicing

Automatically generate invoices when projects are completed in your project management system. Perfect for agencies and development teams.

Client Portals

Build custom client portals where clients can view their invoices, payment history, and outstanding balances.

Financial Dashboards

Create custom analytics dashboards with real-time revenue data, payment trends, and client insights.

Mobile Applications

Build native mobile apps for iOS and Android that connect to your InstaInvoice data for on-the-go business management.

PNGICT Developer Guidelines

For ICT professionals in Papua New Guinea developing integrations with InstaInvoice:

Best Practices

Always validate data before sending to the API to ensure compliance with PNG business standards
Implement proper error handling for network issues common in PNG regions
Cache responses when appropriate to reduce bandwidth usage
Use webhooks for real-time notifications instead of polling
Ensure all financial calculations maintain precision for PGK currency (2 decimal places)

Support for PNG Developers

We provide dedicated support for PNG-based developers and ICT professionals building on our platform. Contact our API team for:

• Technical consultation for integration projects
• Sample code and implementation examples
• Testing sandbox environment
• Compliance guidance for BPNG requirements

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