CloudWatch Metric Guide
Amazon API Gateway CloudWatch AlarmsThresholds, failures, and debugging guides
4 CloudWatch metrics covered for Amazon API Gateway. Each guide includes the recommended alarm threshold, common root causes, and how Nuberio automatically diagnoses it when it fires.
4
metrics covered
AWS/ApiGateway
namespace
5 min
to run a free audit
Amazon API Gateway metrics
Latency
Latency measures the total time between when API Gateway receives a request from a client and when it returns a response. This includes the backend integration time (IntegrationLatency) plus API Gateway's own overhead — authorizers, request/response mapping templates, and throttling checks.
Threshold
p99 Latency > 3,000 ms (3 seconds) for 5 consecutive minutes
5XXError
5XXError counts server-side errors returned by API Gateway in a given period — responses indicating the backend integration failed, timed out, or API Gateway itself hit an internal problem. The Sum statistic gives the raw count; the Average statistic gives the error rate (5XXError count divided by total Count).
Threshold
Average (error rate) ≥ 1% over 5 minutes, OR any 5XXError on low-traffic APIs
4XXError
4XXError counts client-side errors captured by API Gateway in a given period — including throttling (429), authentication/authorization failures (401/403), and modified gateway responses. The Sum statistic gives the raw count; the Average statistic gives the error rate (4XXError count divided by total Count).
Threshold
Average (error rate) rises more than 3x above its trailing 24-hour baseline, sustained for 10 minutes
Count
Count is the total number of API requests API Gateway received in a given period, across all response codes. AWS represents this metric with the SampleCount statistic.
Threshold
Count drops below 50% of its trailing same-hour-of-week baseline for 10 consecutive minutes
Audit your setup
Missing a Amazon API Gateway alarm?
The free Nuberio Audit scans your CloudWatch setup and flags missing or misconfigured Amazon API Gateway alarms in 5 minutes. No credit card. Read-only access.
Looking for alarms across other AWS services? View the full CloudWatch metric guide — thresholds and debugging guides for RDS, Lambda, ECS, ALB, EC2, and DynamoDB.