Google Analytics 4 does not accept custom event names that include spaces. Segment replaces spaces in the Event Name in the Custom Event action with an underscore. As a result, you will see custom events snake cased in Google Analytics 4.

Google Analytics 4 is also case sensitive. If you would like all event names to be lowercase, use the`Lowercase Event Name` settingin theCustom Eventaction. If this setting isdisabled, Googlewill treat event names with different casing as distinct events. For more information, see[Google Analytics 4 Event name rules](https://support.google.com/analytics/answer/13316687?hl=en&ref_topic=13367860&sjid=2167389739796023681-NA#zippy=%2Cweb){:target="_blank"}.

Event names are case-sensitive in Google Analytics 4. If you would like all event names to be lowercase, use the**Lowercase Event Name** settingwhen you create aCustom Eventmapping and select`Yes` from the dropdown. If this setting isset to`No` (`false`), Googletreats event names with different casing as distinct events. For more information, see[Google Analytics 4 Event name rules](https://support.google.com/analytics/answer/13316687?hl=en&ref_topic=13367860&sjid=2167389739796023681-NA#zippy=%2Cweb){:target="_blank"}.