Billable metrics

Billable metrics are the foundation of usage-based pricing in Zenskar. They represent structured values derived from usage events and are used to calculate charges during invoicing.

What is a billable metric

A billable metric is a measurable quantity that captures how a customer uses a product or service. Rather than billing directly on individual usage events, Zenskar transforms these events into billable metrics using configurable aggregation logic.

For example:

  • the total number of API calls made by a customer in a month
  • the peak number of active users on any given day
  • the sum of gigabytes of data transferred in a billing cycle

Relationship between usage events and billable metrics

Usage events record individual instances of customer activity. These may be granular (e.g., “User A made a request at 3:15 PM”) or aggregated at source. Zenskar allows you to define how to process these events into billable metrics using built-in tools.

All billable metrics are defined using one of the following approaches:

  • a visual query builder for non-technical users
  • a SQL-based builder for advanced and custom logic

These tools support standard operations such as sum, count, max, min, and distinct count.

Examples of billable metrics

Example metricDerived from usage events that track…
API callsThe number of API requests made
Monthly active usersThe distinct count of user_id values per month
Peak concurrent sessionsThe maximum number of simultaneous sessions
Storage consumption (GB)The cumulative total of storage_used_gb over the billing cycle

Why billable metrics matter

Billable metrics enable flexible and accurate pricing. They let you:

  • define what counts as billable usage
  • align product value with pricing
  • implement advanced pricing models (e.g., tiered, volume-based, thresholds)

They also serve as a clear, auditable bridge between raw customer activity and the invoice.

Summary

Billable metrics are derived values built from usage events. They abstract the complexity of raw event data into meaningful quantities that directly drive pricing and invoicing logic. In Zenskar, this transformation is fully configurable, giving you control over how customer activity is monetized.