Why do Gmail imports create duplicate contacts from Excel files?

Duplicates appear because Excel doesn’t define unique contact identifiers. When Gmail imports an XLSX file, it often treats similar rows as new entries, especially if phone numbers or emails are formatted inconsistently. A structured contact file prevents this by clearly defining each contact record. Converting Excel contacts to VCF before uploading reduces duplication. Tools like Softaken Excel to vCard Converter help by normalizing contact data and allowing duplicate removal during conversion, which keeps Gmail imports clean and predictable.