Comparison

vCard vs CSV vs Direct Sync: Which Contact Method to Use

By Ayaan Motiwala · Published 12 October 2026 · Updated 12 October 2026 · Editorial review required after material product changes

Every tool that moves phone numbers around picks one of three delivery mechanisms, and the choice determines how much manual work lands on you afterwards. The comparison is short, so here it is up front.

The three ways contact data reaches a destination, compared.

Direct API sync

The tool authenticates to the destination account and writes contacts into it directly. For Google Contacts that means the Google People API, using your own sign-in and a scope limited to contacts. This is what LeadSync does.

What it gets you

• No import step. Contacts exist the moment the run finishes, and sync to your phone through ordinary Google contact sync.
• Duplicate checking before writing. Because the tool is connected to the destination, it can read what is already there and skip it. A file can never do this — an import has no idea what it is colliding with.
• No format corruption. Numbers never pass through a spreadsheet, which is where most damage happens.
• Revocable access. The connection is an OAuth grant you can withdraw in your Google account settings at any time.

What it costs you

• You must grant account access. That is a real decision, and it deserves scrutiny of what scope is requested and what the tool does with it. LeadSync's permission list and the reason for each one.
• No file to keep. If your actual requirement is a portable archive, direct sync does not give you one.
• Destination-specific. A Google Contacts integration writes to Google Contacts. It is not a general export.

vCard (.vcf)

vCard is a dedicated contact format with typed fields — TEL;TYPE=CELL, FN, EMAIL — and it is accepted natively by Google Contacts, iOS and Android. If you need a file, this is the better file.

• Strength: field types survive the trip, so a mobile number arrives labelled as a mobile number.
• Strength: portable and archivable. One file holds many contacts and opens on any platform.
• Weakness: no duplicate awareness. Importing the same .vcf twice gives you two copies of everything.
• Weakness: awkward to edit. It is a structured text format, not a table, so bulk corrections are harder than in a spreadsheet.

CSV

CSV is a table. That makes it excellent for spreadsheets and for systems that want rows, and it is the right answer when the destination genuinely is a spreadsheet or a CRM importer. It is also where phone numbers go to die.

• Strength: easy to inspect, filter, deduplicate and bulk-edit.
• Strength: universally accepted by CRMs and marketing tools.
• Weakness: column headers must match what the importer expects, and Google Contacts' CSV layout is specific.
• Weakness: no field typing, so a mobile and a landline are just two columns of digits.
• Weakness: the format corruption above, which is silent.

If you are stuck with a CSV, do two things before importing: format the phone column as text, and normalise every number to international format so the import does not create duplicates of what you already have.

Which to pick

Pick by destination, not by what a tool happens to offer.

Being explicit about our own boundary: LeadSync does the first row and nothing else. It writes directly to Google Contacts, produces no files, and we point people at file exporters when a file is what they actually need. The full comparison of methods and products sets out where each option fits.