Requirements To Make Custom Fields Filterable
There are two requirements:
Only "Selection" and "Yes / No" custom fields and their answers can be filtered.
The custom field's "Visibility" must be set to "Everyone".
For a complete guide on how to create a custom field, read: Creating Custom Fields
How to Make Custom Fields Filterable
"Selection" Custom Fields
Create a new "selection" custom field in your Control Center > Community Settings > Custom Fields: click the "Create Custom Field" button and select the "Selection" option.
When creating or editing the custom field, in the "Selections" area, make sure the "Make profiles filterable by selection" toggle is on (on by default).
Create a custom field answer by completing the "Selection label..." field.
Adjust individual custom field answers filterable setting (on by default) by clicking the filterable icon 🔍: On (black) / Off (gray).
Create new field answers using the "return" key on your keyboard, or by clicking the "+ Add Selection" button.
Make sure the "Visibility" setting for the custom field is set to "Visible".
Create/save the custom field by clicking "Save Changes".
Any members who complete an answer to this custom field can now be filtered by their selection. Their selection(s) to the custom field will also be show on their member directory profile card.
"Yes / No" Custom Fields
Create a new "Yes / No" custom field in your Control Center > Community Settings > Custom Fields: click the "Create Custom Field" button and select the "On / Off" option.
When creating or editing the Yes / No custom field, in the "Filterable" section, make sure the "Make profiles filterable by selection" toggle is on (on by default).
Make sure the "Visibility" setting for the custom field is set to "Visible".
Create/save the custom field by clicking "Save Changes".
The custom field question with options to filter on "Yes" or "No" will now be available in the member directory filter area.