Understand your cardinality on Grafana Labs

What you're billed for

Thu, 06 Aug 2026 10:05:27 -0400

What’s cardinality?

Cardinality is the number of distinct values an attribute can have. In observability, it determines how many unique series and streams your labels create, and that number can significantly impact your cost and performance.

What you’re actually billed for

A common misconception is that metrics billing is per metric name. It isn’t. A time series is a metric name plus one unique combination of label key-value pairs, and each series that receives data within the last 20 minutes counts as an active series. Grafana Cloud bills metrics on the 95th percentile of your active series count over the billing period, so one metric name with many label combinations can cost far more than dozens of well labeled metrics. The 95th percentile means the top 5% of your usage measurements are excluded before billing, so a brief spike doesn’t set your bill, but a level you sustain does. For example, if you normally run 6,000 active series but spike to 30,000 for 24 hours, you’re still billed close to the 6,000-series rate, because the 24 hour spike is within the forgiven top 5% of the month.

Logs work the same way structurally, though cost attribution is different because it’s purely based on the volume of data processed and ingested. The logs that share one unique label combination form a log stream.

Labels multiply series

Thu, 06 Aug 2026 10:05:27 -0400

Labels multiply series

Labels don’t add series, they multiply them. A status label with 3 values combined with an action label with 5 values produces 15 unique series from what looks like one metric. Add an endpoint label with 3 values and you’re at 45. Every label you add multiplies the count by that label’s number of values.

Cardinality affects cost and performance

Thu, 06 Aug 2026 10:05:27 -0400

Cardinality affects cost and performance

High cardinality affects both your bill and query performance, but metrics and logs are billed differently.

Metrics cost: Grafana Cloud bills metrics on active series, so every unique label combination is a billing unit, whether or not anyone queries it.
Logs cost: Grafana Cloud bills logs on GB processed and ingested, not per stream. High stream cardinality doesn’t add a direct per-stream charge, but it can inflate query costs because larger indexes and more chunks mean bigger scans.
Performance: For logs, many streams mean a large index and many small chunks, which slows queries down. Loki, the Grafana Cloud Logs backend, is designed for low-cardinality labels and limits index labels to 15 by default.

High-cardinality attributes to watch for include user IDs, request or trace IDs, IP addresses, Kubernetes pod names, and timestamps. Any of these used as a label value creates a new series or stream for every unique value.

Explore your cardinality

Thu, 06 Aug 2026 10:05:27 -0400

Interactive guide: Explore your cardinality

The Cardinality tab in the Cost Management and Billing app shows up to 30 days of historical cardinality for your stack, highlights metrics that are new or unused, and links to remediation actions.

Access to the Cardinality tab requires the grafana-cmab-app.cardinality:read permission. Refer to Manage access to the Cost Management and Billing app. If your stack is new or isn’t receiving metrics yet, the tables will be empty or sparse.

Explore your cardinality

Complete this interactive guide directly in your Grafana Cloud stack with an interactive learning experience.

Open in Grafana Cloud

Three questions to ask

Now that you’ve used the Cardinality tab to identify which metrics and labels are contributing to your active series count, ask three questions:

Which metrics produce the most series? They’re your biggest cost levers.
Which labels have the most unique values? They’re the multiplication factors to challenge.
Is anything both high-cardinality and unused? That’s cost with no value, and the easiest win.

Resources

Thu, 06 Aug 2026 10:05:27 -0400

Understand your cardinality on Grafana Labs

What you're billed for

What’s cardinality?

What you’re actually billed for

Labels multiply series

Labels multiply series

Cardinality affects cost and performance

Cardinality affects cost and performance

Explore your cardinality

Interactive guide: Explore your cardinality

Explore your cardinality

Three questions to ask

Resources

Documentation

Community