KNOWLEDGE BASE
Setting Up Google Tag Manager Server-Side Conversion Webhook
The Google Tag Manager Server-Side integration sends conversion events to your GTM server container, enabling server-side tracking.
- Author
- CallGrid Team
- Published
The Google Tag Manager Server-Side integration sends conversion events to your GTM server container, enabling server-side tracking that improves data accuracy and reduces client-side code load on your website.
Prerequisites
Before setting up your webhook, you'll need:
- An active Google Cloud Platform account with billing enabled
- A Google Tag Manager server container deployed and running
- Your GTM server container API secret
- Your Google Analytics Measurement ID (G-XXXXXXXXX format)
Setup Process
1. Get Required Credentials
Find Your Server Container Details:
- Go to Google Tag Manager
- Select your server container workspace
- Navigate to Admin > Container Settings
- Copy the Server Container URL and note the region
Generate API Secret:
- In your server container, go to Admin
- Find the API secret in container settings
- Copy the secret for webhook configuration
2. Create New Webhook
- Navigate to Integrations → Webhooks
- Click + New Webhook
- Select Conversion Pixel template type
- Choose Google Tag Manager from the dropdown
3. Basic Configuration

- Server Region: Select your GTM server region (us, eu, or asia)
- API Secret: Enter your GTM server container API secret
- Measurement ID: Enter your Google Analytics Measurement ID
- Name: Give your webhook a name
- Event: Select Call Completed
- Click Save Webhook
4. Advanced Options (Optional)
After saving, you can configure additional settings:

Dynamic Variables The system automatically maps call data to server-side event parameters:
- VisitorIpAddress maps to client_id for user identification
- InboundNumber maps to user_id parameter
- CallId maps to transaction_id for conversion tracking
- CallRevenue maps to purchase value and item pricing
- UTCUnixTime maps to timestamp_micros for accurate timing
Request Structure The webhook sends Purchase events with:
- User identification data (client_id, user_id)
- Event timing information
- Transaction details including currency and value
- Item-level data for ecommerce tracking
Filtering

- Add filters using any system tag (InboundState, BuyerName, CampaignName, etc.)
- Use Equals conditions to control when events fire
- Combine conditions with Add Or Rule or Add And Rule
Testing

- Fill in test values for detected variables
- Click Run Webhook to verify the integration
- Check your GTM server container preview mode to confirm data receipt
Best Practices
- Ensure your server container is properly deployed and accessible
- Use consistent client_id values for accurate user tracking
- Configure appropriate triggers in your server container to handle incoming events
- Monitor server container performance and costs in Google Cloud Platform
- Test thoroughly before deploying to production campaigns
Troubleshooting
- Verify your API secret and server region are correctly configured
- Check that your server container is running and accessible
- Ensure your Google Analytics Measurement ID is valid and active
- Monitor server container logs in GCP for any error messages
- Use GTM preview mode to validate incoming event data structure
The integration enables you to move conversion tracking from client-side to server-side, improving data accuracy while reducing the tracking load on user browsers and providing more reliable measurement data.