Hello all, where can find out external id on the customer record?

the external id column from a customer search

I'm checking for 1 particular customer record

for an adhoc check - add '&xml=t' to the url and find the externalID

externalid are not able to view or access thru form UI. You can create/edit customer search, go to result tab, select ExternalId. Save&run saved search. you can also use Record.getValue via scripting. field name:'externalid'.