How to Set Up Slack Alerts for Website Changes
Get instant website change notifications delivered directly to your Slack workspace. This guide walks you through connecting OnChange to Slack using incoming webhooks so your team never misses an important change.
What You Need
- An OnChange account with at least one active monitor
- A Slack workspace where you have permission to add apps
- Permission to create incoming webhooks in your Slack workspace
Step 1: Create a Slack Incoming Webhook
Slack incoming webhooks allow external services like OnChange to post messages to a specific Slack channel. Here is how to create one.
Go to your Slack App settings
Navigate to api.slack.com/apps in your browser. If you do not have an app yet, click 'Create New App' and select 'From scratch.' Name it something like 'OnChange Alerts' and select your workspace.
Enable Incoming Webhooks
In your app settings, navigate to 'Incoming Webhooks' in the left sidebar and toggle the switch to enable them.
Add a new webhook
Click 'Add New Webhook to Workspace.' Slack asks you to choose a channel where notifications will be posted. Select the channel you want (for example, #website-changes or #price-alerts) and click 'Allow.'
Copy the webhook URL
Slack generates a webhook URL that looks like https://hooks.slack.com/services/T00000000/B00000000/XXXX. Copy this URL -- you will need it in the next step.
Step 2: Add the Webhook to OnChange
Now that you have your Slack webhook URL, connect it to your OnChange monitors.
Open your monitor settings
Log in to OnChange and navigate to the monitor you want to connect to Slack. Click on the monitor to open its detail page, then go to Settings or Notifications.
Add a Slack notification channel
In the notifications section, select 'Slack' as the notification type. Paste the webhook URL you copied from Slack into the webhook URL field.
Test the connection
Click the 'Test' button to send a test message to your Slack channel. You should see a message appear in your chosen Slack channel within seconds confirming the connection works.
Save the configuration
Once the test succeeds, save the notification settings. Your monitor will now send alerts to Slack whenever a change is detected.
What Slack Alerts Look Like
When OnChange detects a change, the Slack message includes all the context your team needs to act quickly.
Each alert includes:
Best Practices for Slack Alerts
Use Dedicated Channels
Create separate Slack channels for different monitoring categories. For example, use #price-alerts for pricing monitors, #competitor-updates for competitor pages, and #compliance-changes for legal documents. This keeps alerts organized and lets team members subscribe only to the channels relevant to them.
Reduce Noise with CSS Selectors
If your Slack channel is getting too many alerts from minor changes, refine your monitor to use CSS selectors that target only the meaningful content. This prevents alerts from dynamic page elements like timestamps, ads, or personalized sections. See our website monitoring guide for CSS selector tips.
Combine with Other Channels
For critical monitors, set up Slack as your primary alert channel and email as a backup. This ensures you catch notifications even when you are not actively watching Slack. OnChange supports multiple notification channels per monitor.
Troubleshooting
Test message did not appear in Slack
Verify the webhook URL is correct and has not been revoked. Check that the Slack app is still installed in your workspace and the target channel exists.
Alerts stopped arriving
Slack webhook URLs can be invalidated if the Slack app is reinstalled or the channel is deleted. Generate a new webhook URL and update it in OnChange.
Too many notifications
Adjust your check frequency or use CSS selectors to monitor only the content that matters. Consider switching from full-page monitoring to targeted element monitoring.
Related Guides
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