There are 4 main things that influence Digit's savings algorithm:
  1. Checking account balance
  2. Upcoming income (paychecks or predicted irregular income)
  3. Upcoming bills
  4. Recent spending
Every weekday Digit uses these 4 inputs to try and find a small amount of money it knows you don't need for upcoming bills or spending and more importantly won't feel based on how you've recently been spending money.
If it is able to find some money, Digit will auto-transfer those funds to your FDIC insured Digit account.