I am “mathphobic,” so it’s actually kind of funny how much math I had to do when I was writing SAVE BIG. Fortunately, my husband Kris, a Certified Financial Planner, who I affectionately call “math boy” checked all my figures. In case you don’t have a math boy of your own, here are some calculators to help you figure out some of the savings strategies I’ve suggested. They are organized by chapter and page number so that they correspond with the book.

I’m particularly excited about the calculator that determines how much you can afford to spend on a house based on turning your current rent payment into your monthly mortgage payment and saving up for a hefty down payment. Every other home affordability calculator on the web uses theoretical formulas and percentages rather than real-life numbers you know you can live with.

—Elisabeth