# IP Subnet Calculator

A full-stack IP subnet calculator application with React + Vite frontend and FastAPI backend.

## Features

- ✅ Calculate Network ID
- ✅ Calculate Broadcast Address
- ✅ Show First and Last Usable IP addresses
- ✅ Display Total Hosts and Usable Hosts
- ✅ Show Subnet Mask and Wildcard Mask
- ✅ Identify Network Class (A, B, C, D, E)
- ✅ Detect IP Type (Unicast, Multicast, Loopback, etc.)
- ✅ Check if IP is Private or Public
- ✅ Support both CIDR notation and Subnet Mask input

## Project Structure

```
ip-calculator/
├── backend/          # FastAPI backend
│   ├── main.py
│   ├── requirements.txt
│   └── README.md
└── frontend/         # React + Vite frontend
    ├── src/
    │   ├── App.jsx
    │   ├── App.css
    │   ├── main.jsx
    │   └── index.css
    ├── index.html
    ├── package.json
    └── vite.config.js
```

## Setup Instructions

### Backend Setup

1. Navigate to the backend directory:
```bash
cd backend
```

2. Create and activate a virtual environment:
```bash
# Windows
python -m venv venv
venv\Scripts\activate

# Linux/Mac
python -m venv venv
source venv/bin/activate
```

3. Install dependencies:
```bash
pip install -r requirements.txt
```

4. Run the FastAPI server:
```bash
uvicorn main:app --reload --host 0.0.0.0 --port 8000
```

The API will be available at `http://localhost:8000`  
API documentation at `http://localhost:8000/docs`

### Frontend Setup

1. Navigate to the frontend directory:
```bash
cd frontend
```

2. Install dependencies:
```bash
npm install
```

3. Run the development server:
```bash
npm run dev
```

The application will be available at `http://localhost:3000`

## Usage

1. Start the backend server (port 8000)
2. Start the frontend server (port 3000)
3. Open your browser and go to `http://localhost:3000`
4. Enter an IP address (e.g., 192.168.1.1)
5. Choose input method:
   - **CIDR Notation**: Enter a value between 1-32 (e.g., 24)
   - **Subnet Mask**: Enter a subnet mask (e.g., 255.255.255.0)
6. Click "Calculate Subnet" to see all subnet information

## API Endpoints

### POST /calculate
Calculate subnet information for a given IP address.

**Request Body:**
```json
{
  "ip_address": "192.168.1.1",
  "cidr": 24
}
```
or
```json
{
  "ip_address": "192.168.1.1",
  "subnet_mask": "255.255.255.0"
}
```

**Response:**
```json
{
  "ip_address": "192.168.1.1",
  "cidr": 24,
  "subnet_mask": "255.255.255.0",
  "network_id": "192.168.1.0",
  "broadcast_address": "192.168.1.255",
  "first_usable_ip": "192.168.1.1",
  "last_usable_ip": "192.168.1.254",
  "total_hosts": 256,
  "usable_hosts": 254,
  "wildcard_mask": "0.0.0.255",
  "network_class": "C",
  "is_private": true,
  "ip_type": "Unicast"
}
```

## Technologies Used

### Backend
- **FastAPI**: Modern, fast web framework for building APIs
- **Uvicorn**: ASGI server for running FastAPI
- **Pydantic**: Data validation using Python type annotations
- **ipaddress**: Python standard library for IP address manipulation

### Frontend
- **React**: UI library for building interactive interfaces
- **Vite**: Fast build tool and development server
- **Axios**: HTTP client for API requests
- **CSS3**: Modern styling with gradients and animations

## License

MIT