Changedetection.io: Self-Hosted Website Change Monitoring and Alerts

Why Changedetection.io?

Manually checking websites for updates is tedious. Changedetection.io does it for you:

Price tracking — Get alerted when a product drops in price.
Competitor monitoring — Know when competitors update pricing or features.
Regulatory compliance — Track government policy pages for changes.
API monitoring — Watch JSON endpoints for schema or value changes.
Job listings — Get notified about new positions instantly.

Prerequisites

Docker on any machine.
At least 128 MB RAM.

Step 1: Deploy with Docker

docker run -d \
  --name changedetection \
  --restart=always \
  -p 5000:5000 \
  -v changedetection-data:/datastore \
  dgtlmoon/changedetection.io

For JavaScript-rendered pages, add Playwright:

# docker-compose.yml
version: "3"
services:
  changedetection:
    image: dgtlmoon/changedetection.io
    ports:
      - "5000:5000"
    volumes:
      - ./data:/datastore
    environment:
      - PLAYWRIGHT_DRIVER_URL=ws://playwright-chrome:3000
    restart: always

  playwright-chrome:
    image: dgtlmoon/sockpuppetbrowser:latest
    restart: always

Step 2: Monitoring Strategies

Use Case	CSS Selector	Check Interval
Product price	`.price`, `#product-price`	Every 2 hours
Blog/news updates	`article`, `.post-list`	Every 6 hours
API response	(JSON mode)	Every 15 minutes
Government regulation	`#content`, `.regulation-text`	Daily
Job listings	`.job-list`, `#positions`	Every hour
Competitor pricing	`.pricing-table`	Every 4 hours

Step 3: Notification Setup

Configure in Settings > Notifications using Apprise URLs:

# Email
mailto://user:password@smtp.gmail.com?to=alerts@example.com

# Slack
slack://TokenA/TokenB/TokenC/#channel

# Ntfy
ntfy://ntfy.example.com/alerts

# Discord
discord://WebhookID/WebhookToken

# Telegram
tgram://BotToken/ChatID

Step 4: Advanced Filters

Use triggers to only alert on meaningful changes:

Filter	Example	Purpose
Text added	”In stock” appeared	Product back in stock
Text removed	”Available” disappeared	Product sold out
Threshold	Price changed by >10%	Significant price drops
Ignore text	”Last updated:“	Skip dynamic timestamps

Troubleshooting

Problem	Solution
Too many false alerts	Add CSS selectors to target specific content; use “Ignore text” filters
JavaScript page not rendering	Enable Playwright browser container in docker-compose
Check timing is off	Verify the schedule format; minimum interval is 1 minute
Notifications not sending	Test the Apprise URL in Settings > Test Notification
Page requires login	Use the “Request headers” option to send cookies or auth tokens

Summary

One Docker container monitors unlimited URLs.
CSS selectors target specific page elements to avoid false alerts.
70+ notification services via Apprise integration.
Playwright option for JavaScript-rendered pages.

Frequently Asked Questions

What is Changedetection.io and what can I monitor?

Changedetection.io is a self-hosted tool that watches web pages for changes. It periodically fetches a URL and alerts you when the content changes. Common use cases: price tracking on e-commerce sites, monitoring competitor pages, tracking government regulatory updates, watching job listings, and monitoring API endpoint responses.

Can I monitor specific parts of a page instead of the whole thing?

Yes. Use CSS selectors or XPath expressions to target specific elements. For example, monitor only the price element (.product-price), a specific table, or a paragraph. This prevents false alerts from ads, timestamps, or other dynamic content.

What notification methods are supported?

Email (SMTP), Slack, Discord, Telegram, Ntfy, Gotify, Matrix, Apprise (70+ services), webhooks, and custom scripts. You can set different notifications per watch.

Does it handle JavaScript-rendered pages?

Yes. Changedetection.io supports an optional Playwright/Chrome browser container for rendering JavaScript. Without it, only static HTML is fetched. Enable the browser option for SPAs and dynamic sites.