Billing
LaunchDarkly meters usage with several billing units. Understanding which unit applies to each SDK type and feature helps you keep usage predictable, attributable, and free of artificial growth.
Your available billing units vary by plan. This section covers the common, current units and excludes legacy ones. For authoritative definitions and how each unit is calculated, read the calculating billing documentation.
Billing units at a glance
The common, non-legacy billing units are:
| Billing unit | Applies to | What it measures |
|---|---|---|
| Client-side MAU, or cMAU | Client-side SDKs | Unique monthly active contexts the SDK evaluates |
| Service connections | Server-side SDKs | Time each server-side SDK instance stays connected to an environment |
| AI runs | AgentControl | Each time a model is invoked or a judge runs |
| Experimentation keys† | Experimentation | Unique monthly active contexts in experiments |
| Experimentation cMAU† | Experimentation | Unique monthly active contexts, typically user contexts, evaluated by LaunchDarkly server-side, client-side, AI, and edge SDKs and eligible to be included in an experiment. |
| Observability | Observability | Ingested sessions, errors, traces, and logs |
† The billing unit used depends on your plan and contract. If you have questions, reach out to your LaunchDarkly account representative.
The two SDK usage units grow for different reasons. cMAU grows with the number of unique context keys you evaluate. Service connections grow with how many server-side SDK instances connect and for how long.
This section covers the two SDK usage units in depth. For the remaining units, read the calculating billing documentation.
Outcomes
By understanding your billing units, you will:
- Know which metric each SDK contributes to
- Design context keys and SDK initialization to avoid artificial usage growth
- Use in-platform reporting to diagnose unexpected usage and trace it back to a source
Topics
This section covers:
- Service connections: How server-side SDK connections are billed and how to diagnose unexpected connection growth
- cMAU: How unique contexts are billed and how to keep client-side usage predictable