Hi Jesse,
You can see all of the standard contact fields available in the site designer underneath the standard contact fields header:

Additionally, if you go to do a contact import, it will prompt you to download a sample file and that will show you all of the standard contact fields as well as any custom contact fields that have been added to your account. Importing Event Contacts
The same thing goes for a session import, if you download the sample file, it will show you all of the standard session fields as well as any session custom fields that you have created as well. Importing Sessions
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Julia Plymack
Senior Customer Success Manager
Cvent
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