Transaction amounts on your linked cards are used to calculate your Round Ups. If you make a $2.50 charge on your linked card, $0.50 is added to your Round Up progress bar. When your Round Up progress exceeds $5, Crumbs makes an investment into your selected crypto portfolio using funds from your linked bank account.
You also have the possibility to enable Round Ups multipliers. Learn how you can set up Round Ups Multipliers in this article.