Quotas and limits

To ensure efficient operation, Stackdriver Monitoring imposes the following usage limits.

Custom metrics

Category	Maximum value
Active time series^1	100,000^2
Custom metric descriptors per project	500
Labels per metric descriptor	10
String length for label key	100
String length for label value	1024
Time series included in a request^2	200
Rate at which data can be written to a single time series	one point per minute
Histogram buckets per custom distribution metric	200
Prometheus^3-exported metric descriptors per project	10,000

¹ A time series is active if you have written data points to it within the last 24 hours. The number of active time series is recorded in the metric monitoring.googleapis.com/stats/num_time_series.
² You can write only one data point for each time series in a request, so this limit also functions as the maximum number of points that can be written per request.
³ Prometheus is a monitoring tool often used with Kubernetes. See Using Prometheus for more information.

Monitoring API quotas and limits

Category	Maximum value
Limits to API usage	See the API dashboard. Click an API and select Quotas to see your quota.
Lifetime of API page tokens	24 hours

Data retention

Metric data points older than the retention period are deleted from time series.

Category	Value
Retention of metric data points	6 weeks
Lifetime of API page tokens	24 hours

Resource groups

Category	Value
Number of resource groups per Workspace	500
Maximum number of groups included in an email report^1	10

¹ When you configure Stackdriver email reports (Workspace Settings > Email reports), you can request information on utilization of your resource groups. Due to a limitation in the email reporter, the generated reports include information for only 10 groups.

Workspace limits

A Workspace can contain up to 100 GCP projects. See Using Workspaces for more information.

Limits for alerting and uptime checks

Category	Value
Uptime checks per Workspace	100
Alerting policies per Workspace	500
Conditions per alerting policy	6
Notification channels per alerting policy	16
Notification channels per Workspace	4000
Simultaneously open incidents per alerting policy	5000

Limits for charting

Category	Value
Charts on a dashboard	25
Lines on a chart	300