To find a Gaelic equivalent, you'd need to choose a name with a similar meaning or sound. Some possibilities, depending on the desired meaning and which Gaelic (Scottish or Irish) you prefer, could include:
* Caitríona (Irish): This is a popular and well-known Irish Gaelic name that is often anglicized as Catherine or Katherine, which are related to Katie.
* Caitlín (Irish): Another popular Irish Gaelic name, often anglicized as Kathleen or Caitlin.
* Catrìona (Scottish Gaelic): The Scottish Gaelic equivalent of Caitríona.
* Caitrìon (Scottish Gaelic): A shorter version of Catrìona.
Ultimately, the "best" Gaelic equivalent for Katie depends on personal preference.