How can I merge thousands of CSV contacts into one clean VCF file?

To merge a CSV contact list, which includes thousands of contacts, into one clean VCF file, you can combine them by cleaning the CSV: one contact per row, separate columns for phone numbers and emails, and consistent headers. It takes more time, so you should use a converter like Softaken CSV to VCF Converter that supports bulk processing and manual field mapping, so all contacts are exported into one combined VCF file. This is an offline Windows-based tool that preserves phone labels, international numbers and encoding, making the final VCF easy to import on Android, iPhone, Gmail, or Outlook without errors. You can try it with a free demo.