How does sync.blue® detect duplicates?

What sync.blue® can do

If a contact already exists in the sync target, it will be updated instead of being created as a duplicate. A contact is most reliably recognized based on a unique email address. Therefore, if a source contact already has the same email address as an existing contact in the sync target, it will only be updated, and not created as a duplicate.

What sync.blue® does not do

• Remove pre-existing duplicates in a connected app