---
title: Amazon CloudWatch Synthetics
description: CloudWatch Synthetics runs canaries — scripted probes that periodically check URLs and multi-step journeys — for availability monitoring distinct from deploy canaries.
url: https://www.factualminds.com/glossary/cloudwatch-synthetics/
publishDate: 2026-07-22
updateDate: 2026-07-22
---

# Amazon CloudWatch Synthetics

> CloudWatch Synthetics runs canaries — scripted probes that periodically check URLs and multi-step journeys — for availability monitoring distinct from deploy canaries.

## Definition

**Amazon CloudWatch Synthetics** runs **canaries** — scheduled scripts (heartbeat/API or browser) that probe endpoints and user journeys, emit success and latency metrics, and optionally store screenshots/HAR artifacts. Use Synthetics to detect customer-visible outages even when infrastructure metrics look healthy.

## When to use it

- Tier-1 journey availability (login, checkout, critical API)
- External measurement to complement Application Signals backend SLOs
- SLA reporting that requires synthetic success ratios

## When not to use it

- As a substitute for load testing
- High-frequency browser fleets without a cost owner
- Confused with **deploy canaries** (progressive delivery) — different concept

## Tips

- Prefer API canaries when a full browser is unnecessary
- Page on SuccessPercent with owners/runbooks ([monitoring vs alerting](/blog/aws-observability-monitoring-vs-alerting/))
- Align canary journeys with Application Signals SLOs

## Gotchas

### Serious

- 1-minute intervals across many canaries dominate CloudWatch spend
- Private VPC misconfig causes false failures

## Related FactualMinds content

- [Synthetics production guide (2026)](/blog/aws-cloudwatch-synthetics-canaries-production-guide-2026/)
- [CloudWatch RUM / Web Vitals](/blog/aws-cloudwatch-rum-web-vitals-production-guide-2026/)

## Related AWS Services

- aws-managed-services
- devops-pipeline-setup

## Related Posts

- aws-cloudwatch-synthetics-canaries-production-guide-2026
- aws-observability-monitoring-vs-alerting
- customer-facing-sla-slo-design-aws
- amazon-cloudwatch-pricing-metrics-logs-alarms-dashboards
- aws-cloudwatch-rum-web-vitals-production-guide-2026

---

*Source: https://www.factualminds.com/glossary/cloudwatch-synthetics/*