> [!CAUTION]
> **Caution:** This documentation is for Google Ads API **v24** . The latest active version is [**v26**](https://developers.google.com/google-ads/api/reference/rpc/latest/ReachPlanCostModelEnum.ReachPlanCostModel).

The reach plan cost model for an ad format.

[Proto definition ![GitHub](https://developers.google.com/site-assets/logo-github.svg)](https://github.com/googleapis/googleapis/blob/master/google/ads/googleads/v24/enums/reach_plan_cost_model.proto)

| Enums ||
|---|---|
| ## `CPA` | Cost per action (conversion). |
| ## `CPC` | Cost per click. |
| ## `CPM` | Cost per mille (thousand impressions). |
| ## `CPV` | Cost per view. |
| ## `UNKNOWN` | The value is unknown in this version. |
| ## `UNSPECIFIED` | Not specified. |