CSV is an abbreviation of Comma Separated Values, i.e. values separated by commas.
For example, John Doe, john_doe@email.com, 12345678. Here, Name, Email and Phone are separated by commas.

It fits perfectly into an Excel sheet

Excel, Google sheets and virtually all other programs that handle contacts can export as a CSV file. It is easy for XpressU to import this data, because XpressU knows where to place the name, email and phone number. when it creates a contact. XpressU takes the first column and creates as name, the second column as email and the third as phone no. So the order is important

You can download a CSV example and see how your data should be set up.
Or copy/paste your own data directly into the file and import it into XpressU.

Read more about CSV files here

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