W8: The Wonder 8 Calculator

Tired of dropping $10 on a cheeseburger for no good reason? Or $4 on a White Monster or that fancy coffee?

The W8 Calculator shows you exactly how much those little habits are costing you—day by day, month by month, year by year.

The W8 (Wonder 8) Calculator assumes the user input represents a habitual, unnecessary spending behavior. It calculates the true cost of this habit by multiplying the entered amount by a frequency: daily, every other day, weekly, monthly, or annually. Then, it projects how much that money could have grown if invested instead. W8 bases its projections on the historical performance of the S&P 500, which returned an average of 10.985% annually over the 30 years leading up to December 2024—or 8.262% annually after inflation. These calculations assume dividends are automatically reinvested. All investment projections in W8 use compound interest at an annual rate of 8.262%, providing a realistic, inflation-adjusted estimate of opportunity cost.