> [!CAUTION]
> **Caution:** This documentation is for Google Ads API **v23** . The latest active version is [**v26**](https://developers.google.com/google-ads/api/reference/rpc/latest/ConversionCustomVariableService).

Service to manage conversion custom variables.

[Proto definition ![GitHub](https://developers.google.com/site-assets/logo-github.svg)](https://github.com/googleapis/googleapis/blob/master/google/ads/googleads/v23/services/conversion_custom_variable_service.proto)
The following methods are available for this service:

- [MutateConversionCustomVariables](https://developers.google.com/google-ads/api/reference/rpc/v23/ConversionCustomVariableService/MutateConversionCustomVariables.md.txt)