AzMonitor vs Datadog: Choosing the Right Monitoring Scope

Comparing AzMonitor to Datadog is a bit like comparing a precision tool to a full machine shop. Datadog is an enterprise-scale observability platform that does monitoring as one of many things. AzMonitor is purpose-built for external website and API monitoring. Whether one is "better" depends entirely on what problem you're trying to solve and how much complexity you want to manage.

Scope: The Core Difference

Datadog is a full observability platform: APM (Application Performance Monitoring), infrastructure monitoring, log management, network monitoring, security monitoring, databases, and yes — synthetic monitoring and external uptime checks. It's designed to be the single pane of glass for your entire infrastructure.

AzMonitor is an external monitoring service: uptime, API health, SSL certificates, response time, status pages, and incident alerting. It's designed to answer "is my service working from the outside?" with maximum reliability and minimum setup.

These aren't competing for the same use case. Many teams use both.

Datadog Synthetic Monitoring vs AzMonitor

Within Datadog's synthetic monitoring product, capabilities overlap significantly with AzMonitor:

| Capability | AzMonitor | Datadog Synthetics | |---|---|---| | API tests | Yes | Yes | | Browser tests | Limited | Yes (full browser automation) | | Multi-step API tests | Yes | Yes | | Global monitoring locations | Yes | Yes (75+ locations) | | CI/CD integration | Yes | Yes | | Alert channels | Yes | Yes (through Datadog alerting) | | Status pages | Yes (included) | Requires Statuspage.io | | Pricing model | Simple, predictable | Per-test-run, can escalate |

Datadog's Pricing Reality

Datadog's pricing is famously complex and notoriously difficult to predict at scale. Costs scale with:

• Number of hosts monitored (infrastructure monitoring)
• Data ingestion volume (logs, metrics)
• Number of synthetic test runs
• APM trace volume
• Number of users

Teams frequently experience bill shock when Datadog costs scale unexpectedly with traffic growth. A startup paying $500/month can find themselves paying $15,000/month after a growth spurt — not because they added features, but because their data volume increased.

AzMonitor pricing is based on the number of monitors and check frequency — predictable and calculable in advance.

When Datadog is the Better Choice

You need APM — If you want distributed tracing, service maps, and code-level performance data, Datadog APM is excellent. AzMonitor doesn't provide application performance monitoring.

You need log aggregation — If you want to search through application logs alongside your monitoring data, Datadog's log management is the tool. AzMonitor doesn't aggregate logs.

You need infrastructure metrics — For CPU, memory, disk, and network monitoring at the infrastructure level, Datadog's agent-based monitoring is comprehensive.

You need browser-level synthetic testing — Datadog's browser test recorder allows scripting actual user journeys with full browser interaction. AzMonitor focuses on API and HTTP-level monitoring.

You're already in the Datadog ecosystem — If you have APM, logs, and infrastructure monitoring in Datadog, adding synthetics keeps everything in one place.

When AzMonitor is the Better Choice

External monitoring is your primary need — If you primarily need to know "is my service available from the outside?", AzMonitor gives you this without the overhead of a full observability platform.

Predictable pricing — AzMonitor's pricing scales predictably with the number of monitors, not data volume.

Simpler setup — Getting external monitoring working in AzMonitor takes minutes. Datadog's full setup for comparable synthetic monitoring coverage requires more configuration.

Status pages — AzMonitor includes status page functionality. Datadog integrates with Statuspage.io as a separate product (additional cost).

Team access — AzMonitor's pricing typically includes team members. Datadog pricing can scale with team size.

Using Both Together

The most common deployment pattern for mature teams is using both:

• Datadog for internal observability: APM traces, infrastructure metrics, application logs, dashboards
• AzMonitor for external monitoring: uptime from multiple regions, API health checks, SSL expiry, status pages

This combination gives you:

• External availability monitoring independent of your infrastructure (Datadog agent requires your infrastructure to be running)
• Application-level insight when something is wrong
• External synthetic checks from user-perspective locations
• Internal metrics correlated with user-facing symptoms

# AzMonitor external monitoring (complements Datadog internal monitoring)
monitors:
  - name: "API Public Endpoint"
    type: http
    url: "https://api.example.com/health"
    regions: [us-east, eu-west, ap-south]
    
  - name: "SSL Certificate"
    type: ssl
    url: "api.example.com"
    alert_days_before_expiry: 30

# Datadog internal monitoring (requires running infrastructure)
# - APM traces from payment service
# - Database query performance
# - Container CPU/memory metrics
# - Application error logs

Integration Between Tools

AzMonitor can send alerts into Datadog for unified incident management:

# AzMonitor webhook → Datadog Events API
# When AzMonitor detects an outage, create a Datadog event

curl -X POST "https://api.datadoghq.com/api/v1/events" \
  -H "Content-Type: application/json" \
  -H "DD-API-KEY: ${DD_API_KEY}" \
  -d '{
    "title": "AzMonitor: API endpoint down",
    "text": "The payment API is returning errors from 3 regions",
    "priority": "high",
    "alert_type": "error",
    "tags": ["source:azmonitor", "service:payment-api", "env:production"]
  }'

This allows Datadog dashboards to show correlation between external availability events and internal metrics.

The "Do I need Datadog?" Question

Teams often come to Datadog because they heard it's the industry standard. Before committing to the cost and complexity, ask:

1. Do I need application-level tracing (APM)? — If yes, Datadog or a comparable tool
2. Do I need log aggregation at scale? — If yes, Datadog or alternatives (Elastic, Loki)
3. Do I primarily need external availability monitoring? — If primarily this, AzMonitor alone may be sufficient
4. Do I need infrastructure metrics? — If yes, consider Datadog or alternatives (Prometheus+Grafana)

For many small-to-medium engineering teams, the answers are:

• External monitoring: Yes (AzMonitor)
• APM: Maybe (start with error tracking like Sentry, add APM when needed)
• Logs: Maybe (start with your hosting provider's logs)
• Infrastructure: Maybe (start with basic host metrics)

Conclusion

Datadog and AzMonitor solve different problems. Datadog is comprehensive observability for teams that need visibility into every layer of their stack. AzMonitor is purpose-built external monitoring for teams that need to know their services are working from the user's perspective. Start with external monitoring (AzMonitor covers this comprehensively and affordably) and add internal observability tools as your complexity warrants it. For mature engineering teams, both tools serve complementary roles — AzMonitor for the outside-in view, Datadog or similar for the inside-out view.