> ## Documentation Index
> Fetch the complete documentation index at: https://docs.getlago.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Create billable metrics

> Billable metrics define how incoming events are aggregated in order to measure consumption.

If you want to charge your customers for the use of a particular feature, then
you should create the corresponding billable metric.

<Tabs>
  <Tab title="Dashboard">
    To add a new billable metric through the user interface:

    * Enter its `name`;
    * Assign it a `code` which will be used as the name of the event sent from your
      backend;
    * Add a `description` *(optional)*;
    * Select the `aggregation type` which will define how consumption will be
      measured;
    * Define the aggregation property `field_name` to aggregate on;
    * Define `groups` if you price several dimensions for a same billing component; and
    * Define if this billable metric is `recurring` and kept in memory period over period, or resume to 0 at the end of each period.
  </Tab>

  <Tab title="API">
    Here are a few examples of billable metrics you can create:

    <CodeGroup>
      ```bash Storage theme={"dark"}
      LAGO_URL="https://api.getlago.com"
      API_KEY="__YOUR_API_KEY__"

      curl --location --request POST "$LAGO_URL/api/v1/billable_metrics" \
        --header "Authorization: Bearer $API_KEY" \
        --header 'Content-Type: application/json' \
        --data-raw '{
          "billable_metric": {
            "name": "Storage",
            "code": "storage",
            "description": "Number of GB used",
            "aggregation_type": "sum_agg",
            "field_name": "gb",
            "recurring": false,
            "group": {
              "key": "provider",
              "value": ["aws", "google", "azure"]
            }
          }
        }'
      ```

      ```bash Seats theme={"dark"}
      LAGO_URL="https://api.getlago.com"
      API_KEY="__YOUR_API_KEY__"

      curl --location --request POST "$LAGO_URL/api/v1/billable_metrics" \
        --header "Authorization: Bearer $API_KEY" \
        --header 'Content-Type: application/json' \
        --data-raw '{
          "billable_metric": {
            "name": "Seats",
            "code": "seats",
            "description": "Active seats added",
            "aggregation_type": "unique_count_agg",
            "field_name": "seat_id",
            "recurring": true
          }
        }'
      ```

      ```bash CPUs theme={"dark"}
      LAGO_URL="https://api.getlago.com"
      API_KEY="__YOUR_API_KEY__"

      curl --location --request POST "$LAGO_URL/api/v1/billable_metrics" \
        --header "Authorization: Bearer $API_KEY" \
        --header 'Content-Type: application/json' \
        --data-raw '{
          "billable_metric": {
            "name": "CPU",
            "code": "cpu",
            "description": "Maximum number of CPUs used",
            "aggregation_type": "max_agg",
            "field_name": "total_cpu",
            "recurring": false
          }
        }'
      ```

      ```bash Payments theme={"dark"}
      LAGO_URL="https://api.getlago.com"
      API_KEY="__YOUR_API_KEY__"

      curl --location --request POST "$LAGO_URL/api/v1/billable_metrics" \
        --header "Authorization: Bearer $API_KEY" \
        --header 'Content-Type: application/json' \
        --data-raw '{
          "billable_metric": {
            "name": "Payments",
            "code": "payments",
            "description": "Card payments issued",
            "aggregation_type": "sum_agg",
            "field_name": "amount",
            "recurring": false
          }
        }'
      ```
    </CodeGroup>
  </Tab>
</Tabs>

The next section describes the different
[aggregation types](/guide/billable-metrics/aggregation-types). In addition to this, we have added some
[examples](/guide/billable-metrics/aggregation-types/aggregation-examples) to help you understand the relationship
between incoming events and billable metrics.