README.md

---
title: Fraud Detection
emoji: 🌍
colorFrom: green
colorTo: purple
sdk: gradio
sdk_version: 5.42.0
app_file: app.py
pinned: false
license: apache-2.0
short_description: Financial transactions fraud detection.
---

# 🔒 Credit Card Fraud Detection System

**Instantly detect fraudulent transactions with AI-powered risk assessment**

This system uses an **XGBoost machine learning model** to analyse credit card transactions and predict fraud risk in real-time. Simply enter transaction details and get an immediate risk assessment.

## 🚀 Quick Start

1. **Single Transaction**: Enter transaction details → Get instant fraud probability
2. **Batch Processing**: Upload CSV file → Process multiple transactions at once
3. **Risk Assessment**: Receive colour-coded risk levels with clear recommendations

## 🎯 How It Works

The AI model analyses **40+ transaction features** including:
- Transaction amount and timing
- Card details and type
- Email domain patterns
- Geographic information
- User behaviour history

## 📊 Risk Levels Explained

| Risk Level | Probability | What It Means | Action Required |
|------------|-------------|---------------|-----------------|
| 🔴 **High Risk** | ≥80% | Very likely fraud | Block transaction immediately |
| 🟡 **Medium Risk** | 50-79% | Suspicious activity | Manual review needed |
| 🟠 **Low Risk** | 20-49% | Some concerns | Monitor closely |
| 🟢 **Very Low Risk** | <20% | Normal transaction | Process as usual |

## 💡 Example Use Cases

- **Banks**: Screen transactions before processing
- **E-commerce**: Protect against fraudulent purchases  
- **Fintech**: Real-time fraud monitoring
- **Research**: Analyse transaction patterns

## 🛠️ Features

✅ **Real-time predictions** - Results in under 1 second  
✅ **High accuracy** - Trained on large transaction dataset  
✅ **Easy to use** - Simple web interface, no coding required  
✅ **Batch processing** - Handle multiple transactions at once  
✅ **Professional insights** - Clear risk levels and recommendations  

## 📈 Model Performance

- **Algorithm**: XGBoost (Extreme Gradient Boosting)
- **Training Data**: Thousands of real transaction records
- **Accuracy**: High precision with low false positives
- **Speed**: Real-time inference (<100ms per prediction)

## 🔧 How to Use

### For Single Transactions:
1. Fill in the transaction form
2. Click "Analyse Transaction"
3. View risk assessment and follow recommendations

### For Multiple Transactions:
1. Prepare CSV file with transaction data
2. Upload file in "Batch Processing" tab
3. Download results with fraud probabilities

## 📝 CSV Format for Batch Processing

Your CSV should include columns like:
```
TransactionAmt, card4, P_emaildomain, addr1, addr2, card1, card2, etc.
```

## ⚡ Try It Now

No setup required - just enter your transaction details and get instant results!

## 🛡️ Important Notes

- This is a **demonstration system** for educational purposes
- For production use, implement proper security measures
- Always combine AI predictions with human expertise
- Follow your organisation's fraud prevention policies

## 🔬 Technical Details

The model uses advanced feature engineering including:
- Logarithmic transformations
- Time-based features
- Interaction variables
- Categorical encoding
- Missing value handling

Built with Python, scikit-learn, XGBoost, and Gradio.

---

**Ready to detect fraud?** Start by entering a transaction above! 👆