# changedetection.io — Self-Hosted Website Change Monitoring

> changedetection.io monitors websites for content changes and sends alerts. Track price drops, restock alerts, content updates, and page modifications automatically.

## Install

Save in your project root:

## Quick Use

```bash
docker run -d --name changedetection -p 5000:5000 
  -v changedetection-data:/datastore 
  dgtlmoon/changedetection.io:latest
```

Open `http://localhost:5000` — add a URL and start monitoring for changes.

## Intro

**changedetection.io** is a self-hosted website change detection and monitoring tool. It periodically checks web pages for content changes and sends notifications via email, Slack, Discord, Telegram, webhooks, and 70+ notification channels. Perfect for tracking price drops, monitoring competitor sites, catching restock alerts, and watching for content updates.

With 31.1K+ GitHub stars, changedetection.io is the most popular open-source website monitoring tool, used by individuals and businesses for competitive intelligence, price monitoring, and content tracking.

## What changedetection.io Does

- **Content Monitoring**: Detect any text change on any web page
- **Visual Diff**: Highlighted visual comparison showing exactly what changed
- **CSS/XPath Filters**: Monitor specific page sections (price, stock status, etc.)
- **JavaScript Rendering**: Support for JavaScript-heavy sites via Playwright browser
- **Price Tracking**: Extract and track prices with notifications on drops
- **Notifications**: 70+ channels via Apprise (email, Slack, Discord, Telegram, webhooks, etc.)
- **Scheduling**: Configurable check intervals per watch (minutes to days)
- **Import/Export**: Bulk import URLs, export monitoring configurations
- **API**: REST API for programmatic management
- **Tags & Groups**: Organize monitored sites with tags

## Architecture

```
┌──────────────┐     ┌──────────────┐     ┌──────────────┐
│  Web UI      │────▶│ changedetection│──▶│  Target      │
│  (Flask)     │     │  .io Server   │   │  Websites    │
└──────────────┘     └──────┬───────┘    └──────────────┘
                            │
              ┌─────────────┼─────────────┐
              │             │             │
       ┌──────┴──┐   ┌─────┴───┐   ┌─────┴───┐
       │Playwright│   │ Apprise │   │ SQLite  │
       │(JS sites)│   │ (Notify)│   │ (Data)  │
       └──────────┘   └─────────┘   └─────────┘
```

## Self-Hosting

### Docker Compose (with Playwright)

```yaml
services:
  changedetection:
    image: dgtlmoon/changedetection.io:latest
    ports:
      - "5000:5000"
    environment:
      PLAYWRIGHT_DRIVER_URL: ws://playwright-chrome:3000
      BASE_URL: http://localhost:5000
    volumes:
      - changedetection-data:/datastore
    depends_on:
      - playwright-chrome

  playwright-chrome:
    image: dgtlmoon/sockpuppetbrowser:latest
    restart: unless-stopped
    environment:
      SCREEN_WIDTH: 1920
      SCREEN_HEIGHT: 1080

volumes:
  changedetection-data:
```

## Use Cases

### Price Drop Monitoring

```
Watch: https://amazon.com/product-page
CSS Filter: #priceblock_ourprice
Trigger: Text changed
Notification: "Price changed from $99.99 to $79.99!"
  → Send to Telegram + Email
```

### Competitor Monitoring

```
Watch: https://competitor.com/pricing
CSS Filter: .pricing-table
Check every: 6 hours
Notification: "Competitor pricing page changed!"
  → Send to Slack #competitive-intel
```

### Restock Alerts

```
Watch: https://store.com/limited-edition-item
CSS Filter: .stock-status
Trigger: Text contains "In Stock"
Notification: "Item is back in stock!"
  → Send to Discord + Push notification
```

### Content & News Monitoring

```
Watch: https://gov-website.com/policy-updates
CSS Filter: .content-area
Ignore: .sidebar, .footer, .ads
Check every: 1 hour
Notification: "Government policy page updated"
  → Send via Email
```

## Key Features

### CSS/XPath Selectors

```
# Monitor only the price
CSS: .product-price
XPath: //span[@class="price"]

# Monitor article content, ignore sidebar
CSS: article.main-content
CSS Remove: .ads, .related-posts, .comments

# Monitor a table
CSS: table.pricing-comparison
```

### Notification Channels

```
Email (SMTP)          Slack          Discord
Telegram              ntfy           Gotify
PagerDuty             Pushover       Pushbullet
Microsoft Teams       Webhooks       Matrix
IFTTT                 Home Assistant  Custom scripts
... and 60+ more via Apprise
```

### Visual Diff

changedetection.io shows exactly what changed:
```
Before: "Regular Price: $99.99"
After:  "Sale Price: $79.99"     ← highlighted in green
Removed: "Regular Price: $99.99" ← highlighted in red
```

### API

```bash
# Add a new watch
curl -X POST http://localhost:5000/api/v1/watch 
  -H "x-api-key: YOUR_API_KEY" 
  -H "Content-Type: application/json" 
  -d '{"url": "https://example.com", "tag": "competitor", "minutes_between_check": 60}'

# List all watches
curl http://localhost:5000/api/v1/watch 
  -H "x-api-key: YOUR_API_KEY"
```

## changedetection.io vs Alternatives

| Feature | changedetection.io | Visualping | Distill.io | Huginn |
|---------|-------------------|------------|------------|--------|
| Open Source | Yes | No | No | Yes |
| Self-hosted | Yes | No | Browser ext. | Yes |
| JS rendering | Playwright | Yes | Yes | Manual |
| Visual diff | Yes | Yes | Yes | No |
| Notifications | 70+ channels | Email | Email + more | Flexible |
| Price tracking | Yes | No | Yes | Custom |
| Ease of use | Easy | Easy | Easy | Complex |
| Pricing | Free (self-host) | $10+/mo | Free + paid | Free |

## 常见问题

**Q: 可以监控需要登录的页面吗？**
A: 可以。通过 Playwright 浏览器可以配置登录步骤（填写表单、点击按钮），支持 Cookie 注入和 Header 自定义。

**Q: 检查频率可以设到多高？**
A: 最低可以设置为每分钟检查一次。但建议对大多数网站保持 15-60 分钟的间隔，避免被目标网站封禁 IP。

**Q: 需要 Playwright 容器吗？**
A: 如果你监控的网站是纯 HTML（不依赖 JavaScript 渲染），不需要 Playwright。对于 React/Vue/Angular 等 SPA 网站，需要 Playwright 来渲染 JavaScript 内容。

## 来源与致谢

- GitHub: [dgtlmoon/changedetection.io](https://github.com/dgtlmoon/changedetection.io) — 31.1K+ ⭐
- 官网: [changedetection.io](https://changedetection.io)

---
Source: https://tokrepo.com/en/workflows/ed2533e6-34d8-11f1-9bc6-00163e2b0d79
Author: AI Open Source