API Monitoring Overview
API Monitoring enables you to monitor your REST APIs, webhooks, and HTTP endpoints with full control over request configuration. Unlike basic website monitoring, API monitoring supports custom HTTP methods, request headers, POST data, and response body validation—giving you complete visibility into your API health.
What is API Monitoring?
API Monitoring is designed specifically for monitoring backend services, REST APIs, and microservices. It goes beyond simple availability checks by allowing you to:
- Send custom HTTP requests – Use GET, POST, PUT, DELETE, PATCH, or HEAD methods
- Include request headers – Add authentication tokens, API keys, and custom headers
- Send POST data – Submit JSON, XML, or plain text payloads with your requests
- Validate responses – Verify that response bodies contain (or don't contain) expected content
- Track performance – Monitor response times and get alerted when they exceed thresholds
Use API Monitoring when you need to monitor endpoints that require custom headers, authentication, or POST data. For simple website availability checks, Website Monitoring may be more appropriate.
Key Features
HTTP Methods
API Monitoring supports all standard HTTP methods, allowing you to test any type of API endpoint:
| Method | Common Use Cases |
|---|---|
GET | Retrieve data, health check endpoints, status APIs |
POST | Submit data, authentication endpoints, webhook testing |
PUT | Update resources, configuration endpoints |
DELETE | Test delete operations, cleanup endpoints |
PATCH | Partial updates, specific field modifications |
HEAD | Check headers only, lightweight availability checks |
Request Customization
Customize your API requests to match exactly what your production clients send:
- Request Headers – Add custom headers like
Authorization,X-API-Key, or any custom header your API requires - Post Data – Send request bodies in various formats including JSON, XML, JavaScript, HTML, and plain text
- Content-Type – Automatically set the appropriate Content-Type header based on your selected format
Avoid including production credentials or sensitive data in monitored requests. Consider creating dedicated monitoring-only API keys with limited permissions.
Response Validation
Response body validation allows you to verify that your API returns expected content. This is crucial for detecting issues where an API returns a 200 OK status but with incorrect or error content.
- Contains – Check that the response includes specific text (e.g.,
"status":"success") - Does Not Contain – Verify the response doesn't include error messages (e.g.,
"error")
When validation fails, UptimeDock marks the check as down and triggers your configured alerts, even if the HTTP status code indicates success.
Global Monitoring Network
Monitor your APIs from multiple geographic regions to ensure global availability and detect regional issues:
| Region | Locations |
|---|---|
| Europe | London, Milan, Paris, Stockholm, Dublin, Frankfurt |
| United States | California, Ohio, Oregon, Virginia |
Select specific regions or enable all regions for comprehensive global coverage.
Monitoring Options
Configure your API monitoring with these options:
- Check Frequency – Monitor as often as every 30 seconds or up to once per hour
- Enable Simultaneous Monitoring – Run checks from all selected regions at the same time for parallel comparison
- Verify Down from Another Agent – Confirm outages with a second monitoring agent to reduce false positives
Enable "Verify down from another agent" for production APIs to minimize false positive alerts caused by temporary network issues between monitoring agents and your servers.
Reporting & Analytics
Access detailed reports for each API check including:
- Response Code – HTTP status code and description
- Response Time – Time taken for the API to respond
- Monitor Region – Which location performed the check
- Source Code – Full response body for debugging
- Validation Status – Whether response body validation passed or failed
View historical data, analyze trends, and export reports for compliance and SLA tracking.
UptimeDock provides detailed timing breakdown for each request, helping you pinpoint performance bottlenecks in your API:
| Metric | Description |
|---|---|
| DNS Lookup | Time spent resolving the domain name to an IP address. High values may indicate DNS server issues. |
| TCP Connection | Time to establish a TCP connection with the server. High values suggest network latency or server load. |
| TLS Handshake | Time to complete the SSL/TLS handshake for HTTPS connections. |
| Time to First Byte (TTFB) | Time from sending the request to receiving the first byte. Reflects server processing time—critical for API performance analysis. |
| Content Transfer | Time to download the complete response body. |
| Response Size | Total size of the response body. Useful for detecting payload changes or optimization opportunities. |
Click on any response time value in the check history to see the detailed timing breakdown. This helps you identify whether performance issues are related to DNS resolution, network connectivity, server processing, or response payload size.
Next Steps
- Quick Setup – Create your first API monitoring check
- Website Monitoring – Compare with website monitoring features