How it works Put in your starting amount and then what your expenses would be. The emergency savings calculator does the rest! You will be given a line by line display of what your budget/savings would look like till your money runs out. You can select a starting date and even switch between weeks or months. Example: John wants to create an emergency savings budget and wants to know how much of a savings he would need. Most professional money managers will suggest having a savings of at least 6 months. John’s monthly expenses are about 3000 and he has a savings of about 20000. The calculator would then give him a line by line record of how long that money would last.